The Case of Melissa Casias and the Erased Evidence | Forensic Files

Hi Crime Junkies, I'm your host Ashley Flowers. >> And I'm Brit. You guys, last year I
received an email from a Crime Junkie. A woman named Jasmine wanted help because
her aunt had recently vanished from Taos County, New Mexico and no one could agree on what happened
to her. But everyone did agree to speak with us because at the heart of it, they all say
they want to know what happened to her. Her husband and her daughter think that she left on her own. Other family
believes that she was a victim of foul play. To be honest with you, I don't know what to believe. Each side
believes their theory so fervently that I'm afraid my recounting of the facts as
I know them are going to upset everyone because even the facts don't make sense.
But that usually means that we're missing [music] something, a piece of the puzzle that maybe one of you out
there hearing this right now might have. And there is a small chance that missing
piece has bigger implications than I could have ever imagined when I first read Jasmine's [music] email last year.
This is the story of Melissa Casillas. On the afternoon of Thursday, June 26th, 2025, 18-year-old Sierra Casillas is
working at a coffee shop in Taos, New Mexico when she steps away to check a voicemail from her dad, Mark. Now his
tone is tight, like something is off. He wanted her to know that he'd gotten a call from her mom's supervisor who told
him that Melissa hadn't shown up for work [music] that day. Now to Mark, that seems impossible
because he and Melissa both work at Los Alamos National Laboratory. He is a superintendent, she's an administrative
assistant. They share a car and commute together every single day, including that day. So how could she not be there?
But Sierra already knows something he doesn't, which is that Melissa drove the hour and 15 minutes back from the lab
after dropping Mark off. So, she was there at the house at like 7:30, 7:45-ish [music]
when Sierra woke up that morning, which was way out of the norm, by the way. But, she told Sierra that she had
forgotten her security badge. And since she was back home anyway, she would probably just work remotely or maybe
even take the day off. Now, Sierra kind of assumes that she had done the latter because she saw her mom for a second
time later in the day, just before 1:00 when she'd stop by the coffee shop Sierra works at to bring her lunch.
Plus, she'd texted her about a half an hour after that. So, all to say, like, even though her dad seems worried,
Sierra wasn't. Now, since she's at least had some kind of communication with Melissa in the last hour, Mark asked her
to text her mom. And she's surprised when that little message bubble turns green. iPhone users know what that
means. That message didn't deliver like normal. Phone's like off or there is no like regular service, something.
So, she opens up the location app where she can normally see her mom's face pop up. But, this time
nothing loads. Melissa's location has just stopped transmitting. That's when the worry starts to creep in for her
because her mom never lets her phone die. This is all concerning enough that Sierra decides to leave work early to
make sure that her mom's okay. Their house is just a few miles away. She's there by like 3:30. The family's white
Jetta is there in the driveway. Their dogs are outside alone. And that is a little bit odd since they're really
protective and usually stick to Melissa like glue. But, inside things are even stranger.
Melissa's not there, but lots of her stuff is. On the kitchen table, Sierra finds her mom's work phone and badge,
[music] her keys, and this small gold chain that her mother-in-law gave her that she
normally wears like every single day. Then, in the loft area of their house that what connects to her bedroom,
Sierra sees a paycheck that she had given her mom that afternoon to deposit for her. And finally, she goes into her
mom's office where she finds Melissa's purse, [music] her wallet, and both of her personal cell phones, her old phone
and then her new one that she just replaced it with. When Sierra picks them up, like this is when panic sets in
because both phones show a welcome screen. That backdrop that you see when a device is
brand new, except we know these aren't new. And Sierra realizes that they have been
factory reset, like wiped clean. And when she tries to log into Melissa's iCloud, it seems like the password has
been changed. So, from the house, Sierra frantically calls her dad. He's not far
behind. He'd caught a ride with a co-worker. So, whatever's going on, they can figure it out together when he gets
home. And when he gets there, he walks through the property with a different lens. Mark told us that he is a hunter
and a professional outfitter, someone who takes paying clients through back country terrain. So, he like knows how
to read the land. And right away, he began looking for signs of a struggle. And Melissa's tough, and she's not
someone who would have gone down without a fight. If someone forced her out of the house, there would be evidence of
it. But there isn't. Nothing is missing, and the only thing that catches his eye is
an unfamiliar set of tire tracks in the driveway, but they share that driveway with a neighbor. Now, from what he can
tell, he says they're still unknown, maybe not the neighbor's car, but they look like they might have come from a
Jeep. Not knowing what else to do, Mark picks up the phone and calls New Mexico State Police Dispatch right around 5:00
[music] p.m. New Mexico State Police, this is Thomas. Yeah, this is uh Mark Cassias. Uh you
know what, we're um we cannot locate my wife. Uh we haven't heard from her all day. Uh
from work to work this morning was the last time I saw her work. She My daughter saw her
around 1:00. All her stuff is here in the house, but she's not here and it's just not like her to not call or check
in and and take her purse and her phone and it looks like her phone is been My daughter says it it looks like it's been
reset, but there you know, so we looked all around the house everywhere on our property. We cannot find her or nothing
and I don't know what to do. The car that she was in is parked here at the house.
The keys are here. The house was locked. Uh everything everything was was is here. You know what I mean? So she
she went from the plaza. She came home. The car was here parked in the yard. The
keys are on the kitchen table. What's her name? Melissa Cassias. And we called the hospital to see
because I mean, you know, if anyone No one There's no one in there you know, at all like that cuz we
thought well, maybe if something happened to her. Her purse and everything's here, so no one would be
able to identify her. And all you said was she took was her phone? She didn't take nothing. That's the
thing is her phone and everything's here and she always takes her stuff with her.
My daughter was trying to track her location and they always track each other. Mhm. But her But her phone's wiped. The
thing is well, we can't get in she would never have wiped all the pictures off and all the information off of her
phone. Officers are dispatched to the Cassias home and after getting a quick walk
through of the house, they ask Mark and Sierra to lay out their day [music] in detail. Now Mark says that he and
Melissa left for work early that morning as usual. And we're talking like early early. His shift starts at 6:30 in the
morning. And And they live like over an hour away. >> Yeah, and Melissa was behind the wheel.
And like she always did, she dropped him off at his building at around 6:15 and then she would drive to her building on
campus and park her car there. But today Mark reminded Melissa that he needed to
run to the bank at 11:00, so she agreed to bring the car back to him then. Now, what he didn't know is that she turned
around and went home. We know Sierra woke up at 7:45 to find her mom there, which surprised her. But
when Sierra mentions that Melissa's excuse about like being home was like her forgotten badge, Mark says, "Wait,
that that can't be right." He had watched Melissa hand her badge to security at the guard check himself when
they got to the lab that morning. Mark says that he started calling and texting Melissa at around 10:45, but he wasn't
getting anything back, which he says concerned him cuz A, they normally talk throughout the day. B, more than needing
to go to the bank at 11:00, like she was his ride home, but she seemed to be MIA.
So he eventually asked Sierra to pass along a question to her mom. Should he just find another ride home?
>> And did they often communicate through Sierra like that? >> No, never. So that stood out even if she
didn't think too much of it at the time, but like now it does. And so Sierra reaches out and she gets a response from
her mom. Yes, tell him to find a ride home. That was at 1:33 p.m. Not too long after she'd stopped by to bring Sierra
lunch. >> And why isn't she just answering Mark? This is the thing, I couldn't tell you.
>> I mean, I'd be pissed. Well, Mark says that it wasn't unheard of for him to get
rides home with a colleague, so he says that like I mean, he doesn't say he was pissed or whatever, he just says he
makes this plan, didn't think much more of it until Melissa's supervisor called him at around 2:00 saying that she'd
been a no call, no show, which he says that is what totally threw him for a loop. Now, on the phone with dispatch,
Mark had said that Melissa didn't take anything with her. But when he and Sierra actually look more carefully, a
few small things are missing. Melissa's toothbrush, her reading glasses, and sunglasses. And most
significantly, what they calculate to be a 90-day supply of her thyroid medication.
>> That doesn't exactly scream foul play. No, but Melissa just leaving without a
word to her family does not make sense either. Mark tells police that they were supposed to leave the next morning for a
camping trip. And beyond that, Melissa is a devoted mother. Mark has three daughters from a previous marriage, but
Sierra is Melissa's only child, and the two of them are close in a way that is hard to overstate. Especially after
Sierra survived a car accident in 2022 that killed her best friend, a girl who had been like a sister to her. And from
that, Sierra suffered serious injuries, and the emotional damage lingered for longer than the physical. Like it had
been a rough few years. But things were finally looking up. Sierra had just graduated high school.
She was set to move to Albuquerque in the fall for beauty school so she could become an aesthetician. And Melissa had
planned to rent a two-bedroom apartment there to like stay with her for the first couple of months just to like get
her settled. And Mark told us that he planned to kind of go back and forth. Plus, he tells police that they have a
strong marriage. Melissa has never mentioned wanting to leave him, like never mentioned wanting to leave the
girls, none of it. Like this just doesn't make sense. >> Right, so why would she walk away from
all of that? That's the question that hangs in the air as family members who had gotten word about her being missing
start arriving. Like Melissa's parents [music] and her brother, her sister Trudy, and Trudy's daughter Jasmine.
Melissa's parents, Jose and Joanne Mondragon, live nearby, although they had been in Albuquerque visiting Trudy
that day. But once they heard what was going on from Sierra, they were in the car. And these are long-time Crime
Junkie listeners. So, even in shock, they said that they felt like they were prepared and knew what to do. They
worked the phones during the 2 and 1/2 hour drive to Taos, calling relatives and hospitals, hoping that Melissa would
be home safe by the time that they got there. Instead, they pulled up to a property bathed in police lights.
[music] And they were told to wait outside, away from Mark and Sierra. Now, they don't believe for a second that
Melissa left on her own. Something bad must have happened. And they already have someone in mind, Diego Martinez,
who is Sierra's ex-boyfriend. Now, Diego had been behind the wheel in the crash [music] that killed Sierra's best
friend. He suffered a traumatic brain injury in the crash, and according to the family, his behavior became
frightening. In 2024, Sierra took out a restraining order against him, citing physical
abuse, break-ins, stolen keys, and threats against her and loved ones, including specific threats against
Melissa. Diego had also sent Melissa sexually explicit text messages. And did Mark and Sierra bring him up at any
point, too? Not that I know of. Still though, from the very first night, Diego's name is already on the table.
But before that thread can even go anywhere, something else comes up. Jasmine has been blasting [music]
missing person posts on social media since the moment she understood what was happening. And almost immediately,
someone had reached out. And this isn't just anybody. This is a guy named Lloyd,
who has known both Melissa and Mark since they were children. And he tells Melissa's brother that he
saw Melissa earlier that afternoon walking along a highway close to her house, highway 518, in a spot that is
just a couple of miles away. He says that she was wearing a white sweater, and she was kind of like stumbling or
staggering. And there was this old blue Dodge truck nearby, sort of lurking. Now,
this is where the cohesive story I wish I could tell you fractures right down the middle. Because from this point on,
almost every significant moment in this case is going to come in at least two versions, with plenty of contradictions
along the way. So, let me just lay out the sides for you right now. In one corner, you have Mark and all
four of his daughters, including Sierra. I'm going to call them the Casillas household, even though they don't all
live there. In the other corner, you have Melissa's parents, some siblings, her niece Jasmine, some friends, and I'm
going to call them the Mondragons, even though not everyone on that side carries
that name. And as far as the Mondragons are concerned, this moment, when this tip from Lloyd comes in, is the exact
moment that they begin to become suspicious. Not of Diego, who they'd first told
police about, but of Mark. When that tip from Lloyd comes in, Jasmine rushes to tell police what he
saw. They have to check this out, go to where he saw her. She could be hurt, she
could be Jasmine doesn't know, but this at least is a trail that they can follow, right?
But instead of being excited about the lead, Mark immediately shuts it down. He tells officers there's no way that this
was Melissa, because she wasn't wearing a white sweater that day. Sierra remembers that she had on a light
turquoise top when she saw her like around lunchtime. >> Okay, she could have changed. And also,
he says, Melissa doesn't have a limp. So, in his mind, the top's neither here nor there, because he's like, whoever
this woman is that's like stumbling or staggering, this is definitely not my wife.
>> Unless it is and she got hurt, which is like all the more reason to go check it
out and make sure it's not her. >> Listen, I know. But like, here's the thing, the biggest WTF moment for me is
that police just go along with it. No need to check that out. Mark says it's not her,
we're moving on. You're kidding me. I wish I was exaggerating. But no. What if she got the limp because she like jumped
out of her car? I mean, she could have been drugged. >> The girl could have tripped over a
pebble while just like out on a walk. Like, I could talk about this for hours and we're going to get into it more
later, I promise. But they decide not to look. And in the meantime, that night, when the
Mondragons get to talk to Mark, they're expecting a husband out of his mind with
worry. >> Yeah. Instead, what they get is anger. Mark tells them that he and Melissa had
gotten into an argument that morning before they left for [music] work. He had caught her vaping. They bickered
throughout the entire drive to the lab. [music] And when she dropped him off, she told him to find his own effing ride
home. Wait. Mark didn't mention any of that to police. >> Oh, no. And he doesn't for a while. But
if the Mondragons' account is accurate, it means that Mark knew from the jump that Melissa wasn't planning to drive
him home. Not because of anything that Sierra later relayed in the day. And on top of that, they say that Mark starts
badmouthing Melissa almost immediately, telling them that Melissa had been on a roll with eff-ups lately, that she had
destroyed their finances, accumulating debt, getting backed up on tax payments, And are police searching the place at
all, or are they just taking all these statements that first night? No, they they searched. Mark lets police,
including lead investigator Agent Ezekiel Esquivel Mata. He goes through the house and like they take
photographs. And while there was nothing that stood out to the first responding officer who did that like once over of
the place. You know, when you come at it with an investigator's eye and you like zoom in,
there is more that you pick up on. Like they hone in on a pair of Mark's hunting
boots sitting [music] on his and Melissa's bedroom floor next to a fish tank. Some of the mud on them look
fresh, but Mark insists [music] that he hadn't worn those boots in ages. And he points to what he says is proof, a
spider web inside. Nobody put their foot in there recently. Except when agents look, they don't see any spider webs.
For a man who says that he's been at work at Inside all day, fresh mud on hunting boots is a hard thing to explain
away. Then, when agents review the scene photos the next [music] morning, this is
now Friday, June 27th, they get more suspicious. Right next to one of those boots is a
dried drop of something. Something that looks an awful lot like it could be blood. So
when the Mondragons and Melissa's friends are out canvassing neighborhoods and hanging out missing person flyers,
Mark goes in to talk to police. Agents put the photos in front of him. They ask him about the stain, but Mark says he's
sure that's not blood. But he's getting like more and more agitated as the questioning continues until finally he
asks if he should get a lawyer and he just ends it right there. But they detain him and seize his phone, which is
worth noting because despite what he apparently later tells his daughters, he did not hand it over voluntarily
according to what police told us. They have to apply for a search warrant to get its contents by doing a forensic
download, which that's going to take some time. But one thing they're able to do really quickly while he's at the
station that day is verify his alibi. The lab confirms that he was at work that day And even his drive home is
accounted for because of that co-worker who gave him a ride. He confirms that trip. However, that doesn't close
anything out. No, it doesn't seem like he could have physically done anything to Melissa, but that doesn't prove that
he wasn't involved or that he doesn't know more than he's letting on. So, police get a search warrant for the
comb. They take Melissa's phones, they take Mark's boots, and they run a presumptive test on that stain by the
fish tank, which comes back positive for blood. So, they send out swabs of that for further
testing. Meanwhile, the Mondragons decide to organize a search party, which kicks off at Melissa's parents' house on
Saturday, June 28th. Now, Mark says he didn't even know that that was happening. I guess he stumbled across
news of it on Facebook. But once he does, he shows up. Not to help them look for his missing wife, though.
According to the Mondragons, he comes to tell them that he's figured it all out,
and he is sure that Melissa left on her own. He says he'd spent some time going through her paperwork and discovered
that their finances were in far worse shape than he had actually realized. >> I mean, is he basically showing up and
saying, "Don't look for her again?" I don't think those words, "Don't look for her," came out of his mouth, but he is
there to tell them why he thinks she left on her own. He already told them about the finances, though. Like, he
mentioned it that very first night. >> Right, but he now he wants them to understand like the severity of it,
which he says he is just now finally like getting a good grasp of. Though, like the signs seem to have been there.
So, starting a couple of years back, that's when Mark says he got this humiliating wake-up call. He had taken
some co-workers out to lunch, tried to pay, and his cards were declined. He looked into it and learned that his
checking and credit accounts were overdrawn, and that his savings account had been drained. When he confronted
Melissa about it, she told him that she'd used the savings to pay their taxes. An explanation that he accepted.
But it rattled him enough that he decided to separate their finances. He told us that he took over the major
bills like vehicle payments, health insurance, and he left Melissa to handle the smaller monthly expenses. But by
June of 2025, there were at least two huge signs that things had only gotten worse. One, their wages were being
garnished. And two, their security clearances at the lab had been suspended because of
their deteriorating financial situation. Melissa even had to move workspaces because she no longer had the clearance
required for the office where she'd been working. Then how can he claim that he didn't know how
bad things were? Well, I mean, he's more saying that he didn't realize how catastrophic it had gotten, which is
kind of hard for the Mondragons to believe because the couple had been hit with more than a dozen lawsuits or
claims over the years. Mostly tied to unpaid debts, business disputes, and family matters.
But he maintains that he was in the dark on a lot of this stuff. That Melissa was
like intercepting legal paperwork and hiding letters from attorneys or whatever.
>> doesn't make any sense. Like why would she want to do that? I have no idea. But
either way, like it seems like all of this financial stuff was coming to a head because he says that when he
confronted her about the wage garnishment and asked how they were going to afford Sierra's beauty school,
Melissa told him that she had gotten a lawyer and that they had an upcoming court date to appeal a lawsuit judgment.
But now, he just found out apparently that wasn't true. There was no ongoing appeal. And in all her paperwork, he'd
also discovered that she had applied for a personal loan to cover Sierra's tuition and been rejected. And based on
the dates of things, it looks like she had just gotten that rejection days before she disappeared. Now, on top of
that, Mark tells everyone that things weren't going well for Melissa professionally. Besides the clearance
issue, she had also been flagged for performance problems at work. So, Mark's theory, the one that he's telling
everyone, is that the pressure must have finally just reached a boiling point and Melissa
bolted before it all came crashing down. But, but, he also predicts that she's going to be home before the weekend is
over because she has an important work meeting on Monday. Or, you know what? He floats another
idea. Maybe Melissa loved Sierra so much that she left on purpose so that Mark could declare her dead in a few months
and then collect her life insurance and like set Sierra up financially. What? >> Or, maybe she's just hiding out at her
best friend's house. Someone should probably check there. So, his theory is what? Everything? Everything but foul
play, it seems. Where is he saying he thinks she actually is though? Like, the most likely place? I don't think anyone
gets like a clear answer about that. That's the thing. To the Mondragons, the whole thing sounds less like a husband
trying to find his wife and more like somebody trying to rapidly workshop explanations. On top of that, while he's
coming up with all of the ways that she could have just walked off on her own, he finds time to criticize their search
efforts, saying that they're looking in the wrong places, places Melissa wouldn't go because she didn't know them
well. And he keeps bringing up his confirmed alibi, even though nobody is asking him about it. So, being the crime
junkies that the Mondragons are, they start recording their interactions with Mark in the one-party consent state
of New Mexico. Starting with a call that Trudy made to check on Sierra the next day, Sunday.
And she shared that recording >> [music] >> with us. I'm going to play you a snippet
of that call. In the parks and forests you love, there are stories waiting to be told. I'm
Dilia D'Ambra, the host of Park Predators, [music] a true crime podcast that reminds you
sometimes the most beautiful places hide the darkest secrets. Listen now wherever
you get your podcasts. We know exactly what's going on, but I'm not telling no one [ __ ] Okay. Well, as
long as you're sharing that with the police, that's amazing. Well, you know what I told the cops today I that we
have information. They're not even calling me. I I sat there and knocked on their door yesterday, would not answer
the thing, and I finally told the detective, "If you're going to go over there," I said, "I have a lot of
information, but if I'm going to go over there and you're going to start interrogating me again, I'm not going."
Well, we need to be concentrating on We need to be concentrating on finding her.
What's that? We need to find her. >> there, Trudy. You understand? NO, NO, NO. I'M saying No, what I'm saying is
it doesn't help if you're locked up at the police station. You need You need to be out there
Well, you need to be out there doing I went over there. I didn't know. You guys never told me that this was going on
that this legal search was going on yesterday. I'm like, "What the [ __ ] is going on over here?" I never knew about
that. You I never knew about any of that. No one's telling me what you guys are doing. I could be directing and
saying, "No, focus on this area. Focus like I did the other day." You're telling people all over that don't make
no sense. Well, we're We are very open for you to share with us what you what you want, what you're
willing to. Because, you know what? We awesome. I I understand that that that they that
they said there was some sort of a drop of blood in here. [ __ ] there's no blood in here. And besides, like I told
you the time frame does not match. The only time she could have been hurt by me because I was identified in Los Alamos
No, you were at work. Mark >> Mark, watch Trudy. Let me say something so maybe you'll understand this. It's so
simple. If there was a drop of blood and there was blood in this house, that means I would have had to have hurt
Melissa before we left to work, right? Correct? No. That's why they let me out of over there when they had me over
there. Up I was up in Los Alamos. Obviously, they determined everything was in the time
>> I know you were at work. Melissa was fine at 1:00 in the afternoon in Los Alamos.
>> You were at work. No, no. I know that. They said I had a gallon of blood on the floor and it's
irrelevant to Melissa. >> Right. No, and it makes sense. >> This call goes on for a little while
longer. No matter how upset Mark gets, Trudy [music] tries to keep calm. And she, you know, she's not being
confrontational at all. She is in information gathering mode. She wants to keep him talking. And that's when he
says something that catches her really off guard. Honestly, one of her biggest takeaways is this.
>> And then so I changed the locks to all the doors so she would have to she cannot come in with the key and grab her
stuff and bail. She would have to contact Sierra to open up the thing. We put cameras up and everything to to see
if she was coming in. >> Okay. And you know what? That's a good idea. The cameras. He changed the locks
3 days after she vanished. >> Yeah. Which like, why would he even need to do that if she left her keys behind?
>> Dude, that's the thing. Like, I don't think he ever explains that. I'm like, she left her keys. She couldn't get in
anyway. >> I know. >> Also, I I still don't get where she would go. Like, she didn't take her
phone. It sounds like she couldn't have taken any money. She's got nothing with her.
>> not nothing. Remember, she Well, according to Mark and Sierra, she's missing from the house is what her
toothbrush, her reading glasses, her sunglasses, and then that 90-day supply of her thyroid medication.
>> Even that is like a little weird though, right? Like that's not exactly like a
disappearing packing list. Well, the Mondragons say that from the start they think that Mark was trying to plant the
idea that someone came to get Melissa pointing to those unfamiliar tire tracks in the driveway. Remember as evidence
that another man had picked her up. But the thing is like he doesn't say who that would be though. I mean is he
implying that she like left him for another man? >> It's hard to tell what he's saying
because Mark has offered a lot of theories over the months about where she might have gone. Florida, Arizona,
Washington, maybe she left with the help from a contractor that she was having an
affair with. >> Wait, she was having an affair? No, that's the thing not that anyone knows
of. I think he's just guessing. Says, you know, it could have been a contractor or maybe a hunter she knew or
a photographer from Colorado. Sometimes he insinuates to the family that he knows exactly where she is or who she's
with, but he won't give names which feels so weird to them and weird to me. Even the theory that she would leave him
for another man in general though, I can't really get my head around from his telling. Because in his first interview
he told detectives that their marriage was great. There was nothing wrong there. But that's not what police heard
from other people. Some of whom described Mark as egotistical and controlling. A man who allegedly
emotionally and financially abused Melissa. And people have different understandings of Mark and Melissa's
finances. Some say that she was burdened with paying for everything even though Mark made more money. So sure, she might
have been in debt, but like in their eyes that's really Mark's fault. And yeah, there were lawsuits and stuff, but
records show that the majority of those were against Mark alone. Some people even say that the couple had talked
about splitting up after Sierra graduated. And Mark had basically said that everything was his, so Melissa
should be ready to just move out. So, when Melissa was talking about her plans to stay in Albuquerque with Sierra,
it sounded to them more like a marital separation than than just like this mom helping her daughter get settled, which
is what Mark was saying. >> And Sierra had just graduated, right? >> Like like nearly a month before this.
So, the timing is interesting, which police obviously confront him with. Now, initially, he tells them none
of this is true. And he told us the same thing. Though he acknowledges that Melissa had told people that stuff. But
according to Agent Mata, Mark ultimately confirmed it to police, admitted that he
had encouraged Melissa to leave if she wasn't happy. I mean, so maybe this is why he seems so confident
in this walking away theory? Like he told her to go. >> Maybe, but then why won't he tell people
who he thinks she's with if he thinks that he even has like a sliver of an idea? I mean, here's one of like the
stranger parts of this story. Mark starts putting up these mysterious posts on social media. Coded language he says
that only Melissa could understand. A way to let her know that he's tracking her. Tracking her how? Or to where? I
don't know. He is not an easy guy to get a straight answer from. Well, I'm like thinking back, is he talking about like
a hunting tracking? Like he's like on to her trail somehow? That, yes. And listen, some of her trail that day has
already been confirmed by police. The Cassias' home didn't have surveillance cameras or anything like that, but there
were some outside the shopping plaza where Sierra worked. And there is footage of Melissa alone, seemingly
fine, going to drop off lunch for her daughter. At 12:56 p.m., Melissa's white sedan comes in hot to a handicap parking
spot. Like she bumps into that I don't know what I want to call it a guardrail, but you Like a parking stop.
>> Yeah, like and it's so hard that the whole car kind of shakes. So, she like backs up a little bit. And then like 10
seconds later, she gets out of the car and calmly starts walking down the sidewalk with a sandwich for Sierra in
one hand. Then another camera picks her up in the plaza. We get a better look at her.
She's in that turquoise T-shirt with a sweatshirt or something like that tied around her waist and jeans. And then a
minute later, she is back on that same camera walking back to her car. No sandwich anymore, but she's holding a
piece of paper in her hand, that check that Sierra asked her to cash for her. Now, the parking lot camera picks her
back up getting into her car. But the video cuts off before we actually see her pulling away.
So, I don't know what direction she went in, but she had to have made it home after
this since her car, her keys, her wallet, everything was back there at the house, right?
>> But I don't think Mark believes anything happened to Melissa there, like at the
house. His searches seem to be more focused in the spot along Highway 518 where Lloyd spotted Melissa. Wait, I
thought he was adamant that that could not have been Melissa. Okay. So, Mark told us that when that lead came in
that first night when police were there, he was totally unaware that the tipster
was someone who actually knew Melissa. So, that's like he dismissed it because like he didn't want investigators going
on this like wild goose chase. Again, I still think the reason he dismissed it doesn't make sense, but whatever. But
then he says at some point over the first couple of days, he learned that Lloyd was the caller. And so I guess by
Tuesday, July 1st, enough time had passed that he's at least willing to entertain the idea that maybe it could
have been. So, he drives out to that stretch of highway looking for circling birds, which is like a potential sign of
human remains. >> Right, but that means he's now on board with a foul play theory. No.
>> [laughter] >> I know. Mark told our reporter Nina that he never thought Melissa met with foul
play. But, if Lloyd's tip is true and if Melissa had been injured or abducted, she wouldn't have made it far from that
spot. Like it's summer, it's hot, remains attract scavenging birds. So, that's why he looked there on that
Tuesday morning. Like, you know, in an absence of knowing what happened, maybe everything's possible even if it's not
what he believed. Now, he told us that when he went out that way, he happened to see Lloyd outside in his yard. And
so, he decided to stop by and speak with him. Now, police still haven't reached out to Lloyd at that point, by the way.
This is 5 days after Melissa was last seen. And when Lloyd lays out what he actually saw for Mark, this is when
something shifts for Mark. Because Lloyd says that he never described Melissa as
stumbling or staggering when he spoke [music] to her brother. He tells Mark that Melissa was just there 1 minute,
gone the next. And Lloyd didn't actually see her get into that blue truck that he saw or
anything like that. But like, that is kind of the implication that he's making. >> Wait. So, does Mark think this was
Melissa or not? >> Well, now he seems more convinced that that was her. And if she wasn't injured
or acting odd, it actually plays into his theory that she wasn't in distress. She just like left. And what do the
Mondragons think? They've always felt like this could have been her stumbling or not. But even if she wasn't
stumbling, the Mondragons still believe that she could have been in danger when she was out there. They think everything
about this is screaming foul play. They don't believe for a second that she left
willingly. Every theory that Mark has about her walking away is just that, a theory and a constantly changing one at
that with no proof. So, after this search when Mark comes to them again and he's like, "I found something that makes
me even more positive that she left on her own." I imagine that they're pretty skeptical.
But this time it's not just stories or his word. This time Mark has proof. Armed with information from Lloyd about
exactly where he last saw Melissa and the blue truck, Mark had taken Sierra out to retrace Lloyd's steps. And in
essence, he's trying to retrace Melissa's. Not with old school hunting tactics, he was looking for any house
with a surveillance camera pointed at the road. And dude hit paydirt. He finds a video from a house off of Highway 518
that you have to see to believe. The timestamp is 2:18 p.m. on June 26th when Melissa, alive and well, not stumbling,
comes onto frame. She's alone and walking at a brisk pace. Not as if she's scared or anything, just purposefully.
She's wearing what looks to me like the same outfit we saw her in when she dropped lunch off to Sierra. But now her
hair is pulled back and she's carrying a small backpack on her shoulders. For the Casillas side, this video is
proof that Melissa walked away on her own two feet by choice. And Mark told us he wasn't thinking
about vindication or exonerating himself at that moment, but it's hard to ignore
what this video means. That there might be a whole 'nother side to this story. A
completely different narrative about how and why Melissa went missing that will have you questioning
everything. Melissa Casillas part two, take two, ABC marker. Just when everyone was beginning to
believe that something happened to Melissa in her home, even, video footage emerged that proved Melissa was out of
her house and walking down Highway 518 alive and well. Something her husband, Mark Cassias, has been saying since
early on. And his version of events reads like a completely different book. Not a shady, callous husband who had his
wife killed, but a frustrated one who says that his wife abandoned him and their daughter, leaving behind not so
much as a note or explanation. [music] Even then, though, Mark says that some of the allegations against him aren't
just misinterpreted, they're downright wrong. So, let's go back to that first night when police were there and the
Mondragons showed up and told us that Mark was hostile and bad-mouthing Melissa. Mark told us that never
happened. He says that he didn't speak with them at all that night. [music] He was completely focused on dealing with
police. Then there's that argument that we're told he and Melissa had that morning about the e-cigarette, right? He
like caught her vaping. >> Mhm. It takes him a few interviews to come clean about any relationship issues
to police, but he says that he only withheld that information because he wanted them focused on finding Melissa,
not eyeballing him. He also says that this like fight or argument wasn't some big blow-up, just this like minor like
marital spat. And he denies that Melissa ever cursed at him or told him to find his own ride home.
>> Well, didn't that come from him in the first place? >> Well, that's what the Mondragons say,
that he told them that. But, when we talked to him, he said, "No, that's not true. He never said anything like that."
We also asked him about an early theory he apparently mentioned, the one that really rubbed some people the wrong way,
right? About Melissa making herself disappear so that he could declare her dead and then get the life insurance
money for Sierra. Now, Mark, to us never really confirmed or denied whether or not he said that, but what he did tell
us is that he knows a person has to be [music] missing for years before any of that becomes legally relevant anyway.
And actually, police come to learn that Melissa didn't even have a life insurance policy anymore. I mean, she
used to, but that policy expired years ago. Though, I'm not really sure if Mark knew that. And Melissa's financial
records showed just how bad things had gotten. Investigators find out that she had negative account balances that
swallowed up half her paycheck the second they hit and maxed out credit cards that she hadn't made payments on
in months. And let's talk about the physical evidence, like the muddy boots, right? Mark says that he had recently
asked Melissa to refill the fish tank, which was right above where the boots were sitting. And so, he thinks that
maybe she might have spilled [music] water and re-wetted like old dried mud that was already on them from like a
previous hunt. Which investigators think is plausible. >> And the boots mattered like a lot less
once his alibi was confirmed though, right? >> Yeah, and like the same logic I think
then extends to the blood if it's even human blood. We actually still don't know that for
sure because what we know is they did that presumptive test. It is blood. Police still didn't have the lab results
back when we last spoke to them. But Mark is saying, "Listen, that could have come from processing game or even from
their dog." But either way, it's hard to make it mean much when we now know, to your point, Melissa was clearly alive
and walking on her own after she left the house. >> Well, and even if it does come back as
her blood, like she lived there. And there's that, right? It's not like it's like this pool or anything.
>> Right. So, blood and boots, put those aside. >> Mhm. There's also the tech of it all.
Investigators find out that Melissa emailed a coworker the morning of the 26th saying that she was going to be
late because something had come up with her daughter Sierra. That wasn't true. So, it seems like Melissa was telling
[music] everyone a different story so that she could make herself free that day.
>> Mhm. Mark, TBD exactly what she said to him in the car on the drive there, but
like he seemed to think that she was going to be at work. >> Mhm. She told Sierra that she'd come
home because she forgot her badge, which she had with her, we know. But, she told
her job something was up with her daughter. And then, what they pull from her phones, this is the detail more than
anything else that makes me think Melissa had some kind of plan. Cuz forensic downloads show that both of her
phones, they weren't wiped clean at the same time. The older phone that she had,
the one that she'd already replaced, that was factory reset at 8:02 a.m. And then, her newer phone was wiped at
1:38 p.m. I obsessed over this because my gut tells me that if someone else wiped the phones, I would think that
they would have wiped them both at the same time, right? I mean, unless they didn't know that she had two
phones. Like, wiped one thinking it was the phone, realized their mistake, and had to come back and wipe the second
one. >> we know that Melissa must have reset that first phone at home, right? Because
remember, she's there when Sierra woke up at around 7:45, right? So, the one that she doesn't use, like in my mind,
the one she doesn't use or she's not going to need that day gets reset in the morning.
>> Mhm. Just get it over with. Then, she has her phone through the day as she's like bringing Sierra lunch, right? You
can't even say someone else has her phone is like sending these messages. We have her on video bringing Sierra lunch
at 1:00. Then, Melissa sent her daughter that last text message at 1:33. And I mapped everything. Like, all of
that lines up to where if Melissa is at home when that reset happens at 1:38, then she could have very realistically
left then and then been at the spot she is seen at on Highway 518 on camera at 2:18. That's all the things that make me
believe like it had to be her who reset them. But why did she reset them? This is the
thing. I don't know. I mean there I mean I I I feel like there's two scenarios, right? Like if if she reset
them, two scenarios. And like in those scenarios, it's her walking away, right? Like so one, she took her own life, in
which case I don't know why you would have to wipe all of your devices. >> I mean, unless you were hiding stuff you
didn't want anyone to ever find out about. >> when you leave a note for that? Like it
to me this is like if you're if if you're so overwhelmed by like your marriage or your financial situation or
whatever, like why do you have to like why would you leave this mystery behind? Like so it to me this doesn't make a ton
of sense. So the second option is she walked away to start over, to live somewhere else, be with someone else,
whatever that looks like. And in that scenario, maybe something on those phones would have told people exactly
where she was going or like given away a plan that she didn't want found out. And
have police pulled her iCloud data? Oh, this is where it goes like a layer deeper. They tried. Okay. She didn't
just wipe her phones. Apple told them >> [music] >> that her backup had been completely
scrubbed, too. Like her iCloud with nothing left to recover. I didn't even realize that was possible.
Is that actually possible? Agent Ezekiel Esquivel Mata says that that level of digital erasure takes intention. Like
it's more than just hitting a few buttons on an iPhone. >> Yeah. So, he does think though that like
Melissa would know how to do it or I assume at a minimum could Google it. This is not like an impossible thing to
do. It's like supposed to be your data. You should be able to erase it. >> Right. So, is everyone pretty much in
agreement that Melissa is the one that wiped everything? >> Not necessarily. No, like the Mondragons
really wanted investigators to geofence the Cacias' home to see if maybe other devices connected, like either to her
device or the internet or whatever Google around that time. But, Google actually stopped providing that data to
law enforcement in 2024. But, they're really adamant they don't think that Melissa would have done this. They say
that she was very sentimental, like person who held on to every photo and every memory. And so, they can't imagine
a world where she would decide to erase all of that. And really, that disagreement over what Melissa would or
wouldn't do, over who she really was, I think that's really at the heart of everything. Because the tension between
the two sides in this case goes way beyond the investigation. [music] Mark and his daughters say that the
Mondragons spent years shunning Melissa over her separation from the Jehovah's Witness faith. That they barely knew
Sierra, didn't even meet her until she was a few years old. And they claim that they are only now presenting themselves
as people who were like central to her life. But, we asked the Mondragons about this and they totally deny that. They
say that Melissa was very present in their lives. There's regular calls, overnight visits, helping with medical
appointments. Like, Melissa had taken time off work to take her mom to the hospital for a knee replacement and then
she was going to take care of her after that. That appointment was scheduled for
June 30th, four days after she vanished. But, whatever the truth is about those relationships before June 26th, the
aftermath made everything worse. Mark and his daughters say that the extended family cut them out of the search
entirely, withholding incoming tips, blocking them from the Find Melissa Facebook page, and launching a GoFundMe
without ever consulting them. Now, the Mondragons say that donations will fund a reward for information leading to
Melissa's safe return, but Sierra feels like they exploited the tragedy, basically. The Casillas side also says
that the Mondragons fueled rumors that Mark was abusive and directly involved in Melissa's disappearance. Both things
that he and his daughters vehemently deny. Then there are the search efforts themselves, which the Casillas side
thinks the Mondragons wasted critical resources on, directing people to places Melissa would never go, they say. And
they blame her brother for bungling that whole Lloyd tip early on. I mean, the whole stumbling, staggering description,
Agent Mata says that was the reason investigators didn't follow up, not a contributing factor, the deciding
factor. And more than that, according to Mark, Lloyd told him that the blue truck
that he saw was a newer model, not an older one like the family had originally relayed. So, like Mark, Agent Mata
blames a chain of bad details that cost them days. >> But let's be real here, it was still
Mark who told police not to check it out in the first place. And like >> Yeah. since when does the missing
person's spouse call the shots during an investigation? Like the responsibility's
on the police here. I completely agree with that. And remember, they didn't interview Lloyd until after Mark talked
to him. And I also have to say like a huge part of why I think there is such a great divide between families
is that the investigation has not felt robust. Like it leaves each family feeling like enough isn't being done,
which leaves so much room for suspicion and speculation. Like forget the Lloyd of it all, right? Like you took Mark's
word, you didn't talk to Lloyd until like after Mark did, days later, fine. There was this other tip that came in,
and I was shocked at how it was handled. So, a couple of days after Melissa disappeared, this tourist was near a
church in Taos, New Mexico, when she noticed a man on horseback who appeared to be praying. It was an interesting
sight, so she decided to take a photo of him. But then she noticed that he seemed to
be crying and apparently was intoxicated. So, she approached him and asked if he was okay, and he told her
that they had been searching for his missing cousin up in the mountains [music] and that he'd found her body
decapitated. Now, I don't know if he gave a name for this so-called cousin before he rode off, and
that tourist didn't know what to make of that interaction. She like didn't have any context. But later that night, she
saw a missing person poster for Melissa, and I guess she put two and two together, so she reported the encounter
to police and gave them a copy of the photo that she had taken. Investigators showed them to Melissa's
family, and they weren't related to the man, but they did know him. Her brother recognized the guy as 64-year-old Rick
Valerio, known as Wild. He works with horses near a local golf course. And guess what he drives?
A blue Dodge truck. Agent Mata went to speak with Rick on Monday, July 21st. >> When did they know about this tip? So,
that part's unclear. The family seems to think that it was right away, but Mata insinuates that it was later, which is
why they're not talking to him for like a month. But I don't want to get hung up
on the police response time, because I think the proper thing to get hung up on is the interview itself. Because
according to police, once they talked to Rick, he admitted that he helped with search efforts, but he denied everything
else. So, they just dismissed the lead. They think Rick concocted the story for attention.
So, the Mondragons actually got the body cam footage of this interview that makes
them like rule him out. And be prepared to scream. I'm going to play you the entire
interaction between Agent Mata and Rick Valerio so you can make your own determinations about the questions asked
and the answers Rick gave and the conclusion that those led police to. It's still daylight when Agent Mata
pulls up to Rick's home and calls out to him. Valerio, state police. Mata won't ever enter Rick's home and
Rick never fully comes outside. As far as we know, the whole interaction takes place with Rick fully or partially
behind his metal gate door. >> Richard home? Yeah, I'm Richard. Hey Richard, how you doing bro? I'm Agent
Mata, we're state police, bro. Uh You're not in any trouble, bro. I'm here just doing some follow-up with you.
No. Yeah, we we heard, bro, that uh you were talking about finding a decapitated
body out in the Monte, bro. Or what? That you found a uh decapitated body without its head there in the Monte. No,
no, I didn't. Are you sure? >> I'm sure. Cuz I tracked it down to you, bro. The people that heard it took a picture of
you on a horse there in the plaza. You're cruising around on your on your caballo on rojo. Yeah, but I'm going to
plaza. Yeah, here right here in the church, bro. Yeah. No, I don't think I know.
I was I was helping with our search here over here. Yeah. When uh you were there, I guess, you know.
Uh one of one of the days over here in the search and rescue. Yeah. A couple of weeks ago. Yeah. I was helping with them
there. Yeah, but you didn't find anybody without their head, bro, cuz that's what
I'm hear- hearing and that's why I'm here No. to see what's going on with that, bro. No, no, I don't. Are you
sure? >> I'm sure, bro. Yeah, cuz I wouldn't be bugging, bro, if the information didn't
sound pretty serious. That's why I'm here wanting to hear it from you. Mata, but I'm Agent Mata, Mr. Richard.
Nothing. Uh what what would I hear that then? I don't know, bro. And and and this is what I heard, bro,
that you're you're cousin to Melissa and that she's been missing for a few days.
And and that you were up in the Monte and that you were all sad because you you found her you found a a dead body
without its head and that the head was just tossed there to the side, bro. >> I don't even know her. You don't know
her? You were just helping with the search. Well, yeah, I work I work for the state guys over here.
>> Yeah. No, I don't even know her. I'm not even related to her, nothing. Okay. Uh do you remember what you were
doing on the 26th of last month, bro? That's a Thursday. I think I was in Albuquerque, actually.
You're in Albuquerque and that blue Dodge is is yours? Yeah. Okay. So, you didn't go picking up no girls or
anything down there on 518, bro? Nada. Nada. Okay. No, I swear. No, no, you're good. I'm
just trying to sort it out, bro, porque ya sabes, man, people freaking talk and your name came up, bro. Your name came
up that you had information about a dead body and stuff. So, I'm like, okay, well, let's talk, man. Let's see a ver
que. Cuz at the end of the day I got a job to do, you know, and I just got to try to follow up with everything that I
get. No, I don't even know nothing about that. No. Nada, bro. Okay. Richard, what's a good phone number for
you, bro, in case I have questions? >> [snorts] >> What have you heard, bro? Nothing. You haven't heard anything?
>> know her, actually. Or he or the house. Oh, you said you were helping out, bro.
I'm sure you heard something. I heard about it. Yeah? But, uh I work for the state guys, you know. Mhm. And we had
some problems with the beaver pond over there. Yeah. And uh I There was an officer over there
and the search and rescue. Mhm. His name uh What was the guy's name? No, you guys had just showed up there. I
remember talking to you. Yeah. Yeah, but you don't know anything about no dead body, nada, bro?
>> Nada, bro. Are you sure? Okay, >> I just heard just checking bro like I said this information was passed on to
me today and I was like well let's go let's go knock on some doors and see what's up. You can [snorts] give me a
call bro my number Okay, well I know Mr. Richard I'll let you get back to it man.
Gracias. That's it? That's it. It's tell me there was a follow up. Agent Mata says that he did speak with
Rick again at some point but I don't know what came of it and we don't really know much about Rick even. Old court
records from the 90s mention multiple DWI charges. I don't see anything violent on his record but there is some
weirdness here right? But like I don't know how you can ignore and pieces that deserve I believe more investigating. I
mean this bizarre statement allegedly about a decapitated body, the odd behavior the blue truck I mean did they
look at the truck? Like what if he hit Melissa? Yeah there's no looking into the truck as far as I know. But I mean
like the idea of like him knowing he has like DWIs hit her I think it's an interesting theory like Rick related or
not. People said that Melissa used to walk on highway 518 before. Is it possible that she was just out there for
a walk and some kind of accident happened? Yes maybe that's possible but then even in that theory I come back to
the phones. You don't wipe your phone and your iCloud if you're just going to go on a walk. This Rick thing it might
be nothing but this whole interaction that Mata had with Rick I think this is what cast a shadow over everything now
to me because when they say that a lead went nowhere or that they cleared someone
I question what that means. >> Yeah. How deep did they really go? Like another example remember Diego? The very
first person that Melissa's family was suspicious of before they ever were questioning Mark. This is Sierra's
ex-boyfriend who after the car accident had like some brain damage and apparently had been making threats,
sending Melissa like sexually explicit text messages. Well, another agent who worked the case said that Diego wouldn't
speak to them at all. But then agent Mata says that Diego did give an initial statement by phone. And I guess he
explained away the explicit text that he sent Melissa. He told police that he meant to send it to someone else. But
then when investigators tried to get him to give a formal statement, Diego said that he couldn't [music] make it. Then
he told them that he wanted his attorney to be with him. But he never said who his attorney even was. And it doesn't
seem like police are pushing. Now, we couldn't get in touch with Diego, and I'm not saying that he's involved. I
just want to be able to close the loop on some [music] of these things. But I keep finding that really hard to do.
Though for what it's worth, Sierra doesn't think that Diego had anything to do with her mom going missing. She
doesn't see how he could pull something like that off. Now, for all the things that I think may
not have been done, I do want to highlight the things that were. [music] Police poured a lot of resources into
the physical search for Melissa. They used helicopters, drones, tracking and sent canines all through the dense
mountainous terrain around Highway 518. Although official searches didn't start until days after she disappeared. But
they ran facial recognition alerts across the nation. But to date, nothing has ever come of that. And there's been
no bank activity, no passport applications in Melissa's name, no driver's license changes, no
prescription refills for her thyroid medication, which she needs as a thyroid cancer survivor. So, there is just no
trace of her anywhere. But the Casillas side, they do still think that she's out there living
a new life. Mark's most developed theory to date is that Melissa connected with someone through a job that she had
applied for shortly before she disappeared. A position with a Los Alamos subcontractor. He thinks that
whoever she met through that process offered to help her escape her financial situation, like gave her a job, helped
her disappear. And to Mark, that idea gets some fuel from someone commenting on social media claiming that Melissa is
safe in Seattle where that company has ties. [music] Now, investigators confirm that she did apply for this job. She was
even selected for the position, but the company told police that they never managed to reach Melissa to even extend
the offer. She had already vanished by then. And according to Melissa's sister Trudy and her daughter Jasmine, they say
the position was actually based at the same Los Alamos site that she had already worked at. So, she wouldn't have
needed to go anywhere for it. And there's one more thing that makes Mark certain that Melissa is fine. It was a
weird interaction that Sierra had with a woman not too long after her mom vanished.
According to Mark and Sierra, not too long after Melissa went missing, this woman and her fiance, or maybe it
was her husband, showed up at Sierra's work out of nowhere. Apparently, the woman was a long-time friend of
Melissa's and she and the guy had driven all the way from Colorado where they live to see [music] Sierra, who, by the
way, didn't even recognize this woman because if the two of them ever met at all, it was when Sierra was really
little. [music] And that's the part of why this whole encounter is so bizarre. So, supposedly, the woman made this 300
or so mile trip to Taos, New Mexico to give [music] Sierra a $50 high school graduation gift,
which I feel like you could have mailed. Yeah. But while she's there, she makes sure to get a photo of her and Sierra
together. And she makes these cryptic comments like I have psychic abilities and I feel
like Melissa is fine. And if your mom really left on her own, she always knows where to find me. She
also told Sierra to keep her visit a secret from Mark, which obviously she did not.
>> Mhm. So Mark starts thinking, maybe Melissa sent [music] this woman as a proxy of
sorts to check on Sierra. They were super close. She really loved Sierra. So like hence the photo. Maybe Melissa
wanted to know that Sierra was okay after her mom vanished into thin air. Now, the kind of strange part to me is
that Mark didn't bring this to police [music] right away. He said that he wanted to wait and see if Melissa would
contact them. But after like a week goes by and there is no contact, he finally lets them know. I mean, was she in
contact with that friend before she went missing? Well, Sierra says that Melissa
had reached out to this woman with an invite to [music] Sierra's graduation party, but I don't know if that's
something that the woman told her or if Melissa had relayed that to Sierra at some point. Okay, and like I know
Melissa's phone, both of them, were wiped, but they can still get like call and text
records from like the cell service provider. So we should be able to see like who she was in contact with before
she was vanished, regardless if the phones were factory reset or not, right? >> Yes, theoretically, yes, but last I
heard, her records, and mind you, she went missing June 2025, >> Uh-huh. those records are still under
review. >> [snorts] >> So, I don't know. Ok- okay, and did they get anything from Mark's phone? Agent
Mata told us that there is nothing on Mark's phone that suggests he was plotting against Melissa.
I don't know. >> not an answer. [laughter] >> Well, and I also don't know, like, wait,
so you know, you've been through Mark's phone completely, but not the person who
actually went missing. And I know, like right Mark had his physical phone. I don't know, priorities? Yeah, I don't
know I don't know what's going on there. Obviously they would have to get a warrant from the cell provider, but like
all this time later I I feel like we should be able to like have some answers about what was on her phone. Now, all in
all, Agent Matta's interpretation of all that he has so far is that Melissa probably left on her own. Police have
not officially ruled out foul play, but Matta's gut says that she's alive. Legally, she's classified as missing and
endangered because of the risk of her being without her thyroid medication, but as far as law enforcement is
concerned, there's no suspect, there's no crime scene, and no evidence that anything
[music] happened to her after that camera caught her on Highway 518. But the Mondragons
think that is dead wrong. And the dominant [music] theory among them still is that Mark is somehow
connected to whatever happened to Melissa in some way. [music] Though they haven't ruled out other possibilities
including a random abduction while Melissa was out walking. The only thing that they feel certain of is that
Melissa would not willingly abandon the daughter that she loved so much without a word. Now Mark denies any involvement
and he got pissed when our reporter Nina asked him point blank if he killed Melissa.
He said that no one has ever asked him that before. No one, not even the police? I guess not.
But considering the interview that we saw and heard with Rick, like I honestly, that wouldn't surprise me.
Okay. I I don't know. I don't usually ask this cuz normally I can tell. Uh but I'm kind of dying to know like what
what do you think? This one genuinely has me in knots. Like there are very few cases that have me flip-flopping back
and forth by the day the way that this one does. You cannot argue with that video. Like she
left her house on her own. She had a backpack. She lied to everyone about what she was doing that day.
I do believe that she wiped her phones. It is so easy to look at this and say that she left. Especially the more
stories we hear about other women who have done the same. I feel like mothers have this different societal expectation
than [music] father or like men do and it's hard for us to wrap our minds around a mom leaving. But it does
happen. The story that like everyone is recently passing around about that woman
in North Carolina, that mom who went missing in like 2001. >> Yeah, um Michelle Michelle Hunley Smith.
>> Mhm. So like her husband reported her missing, suspicion fell on him. Everyone
assumed the worst. And then Michelle turned up alive in February of 2026 having quietly built a whole new life
somewhere else for more than two decades. So it's not beyond the realm of possibility. If everything was closing
in on her the way people are describing, is it possible she took her own life? That's the like the one theory that no
one seems to really buy into. Like Sierra is willing to believe that her mom left, but she doesn't think that she
would ever do that to her. She thinks that like kind of what I said earlier, like at least she would have left a
note. She's not going to leave them wondering. And I mean if you're still like asking what I think, I agree with
that, right? Like I keep going back to the phones. Like I don't think you need to wipe your phone
and your iCloud if your plan is just to take your own life. Yeah, but you also don't really need to do that if you're
just walking away. Like just leave them behind. Well, un unless like I said, like there's something on the phone.
There's like communications with someone or something that has to do with a plan.
Now, I'm about to go way out there for a second, so stay with me. Have you seen the connections that people are making
recently around the missing scientists, researchers, [music] military officials? Yeah. So,
for those who are not in the know, this is something to pay attention to. The short version of this is that a
handful of US people connected to places like Los Alamos and NASA have either died or disappeared over the last few
years. At the time that we're recording this, the running list is at 11, and there's this theory that these are
somehow connected to maybe foreign espionage, that like countries like China or Russia are
targeting people with access to sensitive US technology. To me, that's the least scary scenario. The scarier
one is that the call is coming from inside the house, or even that private corporations who make a lot of money and
energy don't want us figuring out an unlock for free energy. And I I'm not just pulling this out of a hat on my
own. So, a former FBI assistant director named Chris Swecker has been vocal about
the links that these people have. All mostly connected, not directly, but like in the type of work that they do. Now,
he's not claiming specific knowledge of any of these individual cases, but he believes that the patterns are
suspicious enough that the FBI needs to stop treating them as isolated incidents
and start pulling resources to look for links. And the feds are apparently involved now. Newsweek reported that the
FBI is investigating the series of cases as of late April. And I bring this all back because Melissa's name has appeared
on this list circulating in news coverage of this pattern. So, we reached out to Swecker directly to see if he
knew anything beyond what was making kind of like the rounds in the tabloids and stuff.
He didn't, but he did clarify that he's not suggesting that all of the cases are
connected, which I feel like is like what they were saying. >> to say which [laughter] is yeah, feels
confusing. According to various news coverage, on paper a few of these cases have already been explained away.
A drowning, a murder by a former classmate, cardiovascular disease, a suicide. But Swecker's bigger point was
more like they might not all be connected, but like everyone counted in this potential group worked near or with
sensitive stuff. And he says that foreign intelligence services will go after people in those positions, even
admins, because they like know who's in what meetings. They know who works where. They know what schedules look
like. Melissa Cacias, that was her role. She was an assistant admin. So, what information would she have had access
to? As you can imagine, I don't have the clearance to know that. I don't even know, truthfully, if police could get
clearance to know that. >> Right. And listen, the timing is weird around when she goes missing.
Like we don't have time to go down the whole list, but I'll give you like a few examples so you kind of get a sense of
what people are talking about online. So, on May 4th, 2025, this is a month and a half before Melissa goes missing,
a retired Los Alamos employee named Anthony Chavez walks out of his home leaving behind his wallet, his keys, his
cigarettes, car in the driveway, no cell phone, disappears. Then, on June 22nd, 2025, this is just a few days before
Melissa goes missing, 60-year-old Monica Reza went hiking with two companions. At
some point, one of her companions was like 30 ft ahead of her. He turns around, gestures to show her like which
direction to go in. She acknowledges him. Moments later, when he looked back again, she's gone. Has not been seen
since. What? Now, that was in California, not New Mexico. And Monica worked for NASA, not Los Alamos. But
then you have Melissa going missing June 26th, and then closer to Melissa's home,
William Neil McCasland, a retired Air Force Major General who once oversaw the lab that funds work in the same
aerospace field that Monica worked in, he goes missing February 27th, 2026. Walks out of his Albuquerque, New Mexico
home with a gun and his wallet while leaving behind his phone and other belongings. And then poof, gone. Now, I
mean, you can see this is very tenuous. >> Mhm. But the coincidences have people
asking questions. Melissa especially could have been an easy target if she had the right information or
connections, right? Like she was in a bad financial spot. Someone promises her a new life or a new start. Okay, but
she's identified as a good target by someone. They see all the trouble she's in, they offer her a way out, she takes
it. What, leaving her family behind to clean up the mess? Yes. But like I mean, she Her family's
going to have to clean up the mess if she just walked away on her own. Like so I mean, to me that's not like any less
of a reason why she wouldn't have have done it. And remember, her and her husband, they just got their clearance
taken away. I'm telling you like, I don't know. And this could like begin to explain how she could start
over without her ID ever popping up. Like how she'd get more meds. Like she would have this whole new identity. Like
in a way easier way if someone's helping you, right? Like I, no matter what, if she walked away, I think she needed
someone's help to do that. But then, come back to the phones. It's always like the phones for me.
If she walked away, connected to this thing or not, why wouldn't she just take her phones and
get rid of them? Like I know I like I know you don't want to keep them. >> Well, like right, like keeping them
keeping them active, tracking, right? So like factory reset them, but toss them in your bag and get rid of them
somewhere else. >> Dump them in in some water, like put them in like in the mountains, like put
them in a dumpster. Like there's something about that part that like or even like
leaving her phones is like is that like a plant? Is this like a a a weird red herring? Why do you leave them? I mean I
guess unless you want your like them to have like phones are expensive. You leave them behind cuz they're free
phones. So you can get like conspiratorial. But then, you know, you remember that we
see her on camera walking alone after the phones are wiped. And then I don't know, you just keep
going around and like where was she going? Like I just I don't know. I mean I mean maybe
whatever instructions she got for wiping the phone like from we were saying Googling it, but maybe from someone,
whatever. Maybe they said it was better if she left them behind so there was like no way to track
the actual like hardware device itself. Maybe. Listen, it doesn't have to be connected to all these other cases. In
fact, one thing that everyone we spoke to seems to actually agree on, and there are like few of those things, they do
not believe that Melissa is connected to these other scientists or or whatever else is going on. Mark told us that he
thought the theory was BS. Jasmine does not think it holds up either. Mata said specifically didn't even know anything
about Anthony Chavez, who was like the one person I mentioned who was connected to Los Alamos directly, right? But it
would be a completely different jurisdiction cuz he lived in Los Alamos. And when Mata talked about it, he said,
you know, I'll look into it, but he's like, you know, those places are compartmentalized by design. They're set
up so people only know what they need to know for their job. So I am I think he was saying that implying that it's like
unlikely that Anthony and Melissa were on the same thing or >> ever crossed paths, yeah. But I I don't
I again, I don't know anything about the work that she did. And I highly doubt I
will ever know about the work that she did because until her clearance just recently got revoked, like she I think
was working on like high clearance stuff. So, I don't know. Like this missing or deceased scientist thing
it has me down like a genuine rabbit hole. Like I mean, I hope to come back out of it someday with like a more
complete episode on it. But like one, it's a hard nut to crack when practically everyone was working on top
secret and two, I actually think I've already like tripped some wires and you laugh, but like genuinely have
people monitoring what I'm like getting my nose in. So, this is always my reminder to you,
to everyone that like I know how to swim, I love my life, I'm as safe as safe can be. So, like if I so much as
get in a fender bender right now, it should be considered suspicious. Like there was this one scientist who's on
this list, Amy Eckridge, and her case is wild. People should go look it up, but she was on a Zoom call with somebody
that got recorded. And she's like, "The reason I stick my neck out is because at
least if my head gets chopped off, people will take notice. If you don't do that, they bury you and nobody talks
about it." So, in the spirit of sticking my neck out, any Crime Junkies out there who want to
point me in the right direction, tips@audiochuck.com. And listen, while I absolutely believe
that something scary is happening to people who work in aerospace sciences, it's probably not the solution that
we're looking for in Melissa's case. Right? Like if we go Occam's razor, that would suggest that the simplest
answer is likely the right one. Melissa was in a bad financial spot. She was planning to move away when her
daughter went off to beauty school, but the loan application for that had just gotten rejected.
What was she going to do now? She very clearly told everyone different stories about the day that she went missing. Her
phones were wiped. Her iCloud was wiped. And after that, she is seen walking alone down Highway 518. The simplest
explanation is that she chose to walk away and did it on her own. And some days, I really believe that.
But then other days, I'll get a new tidbit of info that makes no freaking sense. Like we've been talking to family
and reporting on this for months and months and months, but right as I was finalizing this episode, Nina pinged me
with another curveball. You know that friend from Colorado that checked in on Sierra? Super randomly with like $50 for
high school graduation gift. We just found out that police did find and talk to that woman. She denied the entire
thing. What? She says she hasn't been to Taos since 2014. She didn't visit Sierra,
denied even knowing Melissa or Sierra, and said that she was confused as to how or why her name was even being brought
up in the investigation. >> Wait. [laughter] Dude, this is But there's like But a-
What? This is the weirdest thing to me. Now, we tried reaching out to this woman, but as of this recording, we've
been unsuccessful. If she hears this, I would love to talk to you. Again, my email tips@audiochuck.com.
>> Wait, so so this visit didn't happen? I don't know. This is like Mark and Sierra
both still say that this thing happened. I just can't get to the bottom of who this woman is. Like did she have ties to
Melissa? And now she's distancing herself. Did she like make up ties to Melissa? And she's
connected to something or someone. If you don't believe that this woman, whoever she is, if you don't believe
she's lying and you want to say that like Mark made the story up, you have to remember
>> Sierra is in on it. Sierra is the one who saw her. Like say whatever you will
about Mark and Melissa's relationship, Sierra and her mom were so close. I cannot imagine why on earth she would
ever make anything like that up. I don't think that that happened. So, are we like circling back to the conspiracy
theory then? I mean like [laughter] It crossed my mind. I don't know what to believe about this woman. I am just
hoping she reaches out so we can sort all this out. Again, I mean we know that like interviews are quick, maybe they're
not thorough, maybe something's lost in translation or missing like a very simple explanation.
I don't know. Do you think that there's any world where Sierra would protect her dad if he [music] asked her
to go along with something? Like she's she's already lost one parent and if everyone is trying to come down on your
dad and you believe in your heart of hearts that he's innocent like if he asked you to do something
>> where you're going but no, like it doesn't it doesn't seem like she would do something like that from talking to
her. But I will say like there is something about Mark that I still just can't quite
figure out. Like I tried to tell this story in as streamlined a way as possible, but there were all these
rabbit holes along the way that often came from stuff that he said or did that was odd but then ultimately led nowhere.
Cuz that kind of like unresolved weirdness is all over this case casting a shadow.
Like for instance and like I didn't even get into this earlier Mark had originally told a story about
the morning of the 26th when he and Melissa drove to work that involved them stopping at this particular gas station
on their way. And so in part of like looking for Melissa and looking into this, police pulled footage, they were
never there. Which seems fishy as hell, except security footage put them both to
like going through the gate at Los Alamos after this, like when she's dropping Mark off at work.
>> Yeah, and like we also see her like the rest of the day until 2:00. >> Yeah, bring She brings her daughter
lunch. She's on camera. She's by herself. She seems fine. So, it it's why I didn't bring it up earlier, it means
nothing. But then you're like, well then where did this even come from? Cuz you're not
talking Mark like a year later. Like it's right when it happened. And then also like what's with him being so
defensive and aggressive? Like I honestly get him acting like that towards us. Like we flat out asked the
guy if he killed his wife, like who he believes walked out on him. But he was like this with her family
long before we came along. I mean, do you think her bringing Sierra lunch was like a little way of saying goodbye?
Like we haven't really talked about like if that was something normal for her to
do. Like if she brought Sierra lunch often, if it was something that they did together. I assume no, because like she
would normally be at work, right? Like we She just doesn't go to work today and that's why she's doing this. And so I
think it's easy to be like, oh yeah, she wanted to see her one more time. But like if this was a goodbye, it was the
shortest goodbye ever. Like she is literally in and out giving her the sandwich in like a minute.
So, maybe maybe she wanted to see her one time, maybe not. Like I feel like this is one of those things you could
read either way. Was this just like a mom doing something nice for her daughter real quick because that's just
the kind of mom she was, and it wasn't a long interaction because she planned on
seeing her later at home, or was this a goodbye? One more look at her baby girl who she knew she might never see again.
One quick glance hurried because she had to get moving before her family started
coming home. >> Mhm. Then even that doesn't make sense because why would she wait so long to
leave? Like we haven't talked about that. Like she could have gotten a way better head start if she had left in the
morning. >> Right, cuz she had told so many stories to kind of free up the day, explain
where she was. >> goes to work, she doesn't have to be, as far as I know, seen by anyone. Right. I
am really obsessed with trying to figure out where Melissa was for the rest of the day.
I'm convinced that that has to hold some kind of clue. And interestingly, while we know geofencing is no longer an
option for police like about phone data and who was maybe like around her house,
I don't think phone data is totally off the table. Agent Mata says that there was another company who offered to do
something similar to geofencing for a fee of about 5 grand. But the agency actually decided against it for now.
They said it was partly over the cost, partly because they don't know how it would hold up in court if this case ever
becomes criminal. And I know our listeners are like, "Show up." I'll even talk to the family. I'm like, "Listen,
do we need to like fundraise? Do you guys need the funds?" Like, even if my mom even if you pulled it up in court,
like does it give you something when you have nothing? Either an answer or like a
non-answer, like Right. >> to rule something out, right? >> But I actually think there's like a
better option. So, it sounds like what they were looking at, if it's close to geofencing, is about putting other
phones in proximity to hers or like an area. I am more interested in where her phone was before it was wiped. And I
know that that data is still available. You see, I got schooled recently. I was out in the desert hanging out with some
cadaver dogs and their amazing handlers, as one does. >> [laughter] >> And the woman who was organizing this
search, her name is Candice Cooley. She is a badass. She was always a canine handler, but after her son Dylan was
murdered in 2022, she took her work to the next level. And she created an nonprofit called Dylan's Legacy after
that. And while her work is mostly around dog searches, when you're doing a dog search, you have
to figure out where to start your search, your cadaver search, right? >> And she learned something that she is
now on a mission to share with every law enforcement officer who will listen because it has the potential to be a
huge unlock for investigating cases in the digital [music] age. When it comes to phones, everyone's always thinking
about cell phone providers, towers, pings. And yeah, that usually requires a warrant. But by the way,
all of those apps on your phone, Facebook, Instagram, AccuWeather, you've been giving all of them permission to
follow every step you take if like cookies are accepted. Honestly, sometimes they're doing it anyways.
And that data doesn't just live in your phone. The companies collect it, the companies store it, and in some cases,
they're sharing it or selling portions of it, which means that it's not private data, right? That means that
investigators don't have to rely on cell towers only. They can go to these companies and even though like there's
this common belief that you have to have a warrant to get that data from those companies, that is not true. There are
actually what they call exigent circumstances where you do not have to have a warrant.
You contact these companies, tell them there are exigent circumstances, right? You have a missing person, you're
investigating a homicide, >> Mhm. >> and they can get you like I don't know how much, but for sure
location data that can map where someone was, where were they moving. So take Melissa's case, right? We know she had
Facebook. Mata could request data from Meta, which depending on her settings might include location-related
information from that day, which might clear up a lot. But, knowing this case, it also might
throw a massive curveball into it. >> Honestly, it probably would throw a massive curveball, [laughter] but like
at least we'd be one step closer to the truth. >> Right. Now, the thing is another thing I I need to make sure
people are hearing this mention if this is a new concept to anyone, especially if you're in law enforcement or have a
family who's missing. Even if you get there, right? Like even if you do the exigent circumstances, they give you the
data, what you'll end up with is this massive pile of data points, likely in some kind of spreadsheet. Now,
traditionally, that means that someone has to like sit down, analyze it, which can take time. I mean, we're still
waiting on test results a year later to know what blood was in Melissa's house. >> Right. I don't have high hopes that
police just have like someone on deck to go through data. But good news, it is easier now than it's ever been. There is
a platform called Badger that lets investigators map phone data from carriers, from Google, Snapchat, and
more, track phones in real time, and manage the whole legal process in one place. So, I would encourage anyone
whose loved one vanished with their phone in the social media age to press their detective to look into this. Maybe
it will lead to answers. Maybe it will just lead to more questions, and that's kind of where I am
with this whole case. Every time I think I have a handle on it, something shifts.
A new detail that doesn't quite fit, or a conspiracy theory sweeping the internet that of course has some kind of
Maybe tie or cast a shadow over this case, cuz why wouldn't it? It feels like the farther we get out from June 26,
2025, the further we are from any real answers. But I think real answers are there if we can get more real facts. We
don't know if Melissa walked away from a life that had become unbearable. We don't know if someone made sure she
couldn't come back. We don't even know why she was on Highway 518 on the afternoon of June 26th, 2025.
We just know that she was there and then she vanished. We spoke to a lot of people for this episode. Mark, Sierra,
Melissa's parents and siblings, her stepdaughters, her niece Jasmine, some friends,
and the two sides disagree on almost everything. But strip it all away and everyone says some version of the same
thing. They just want to find Melissa. And if she is out there, all they're asking is that she lets them
know that she's okay. Cuz no matter which side they're on, that is the part that's eating them
alive, the not knowing. So if anyone out there knows anything about what happened to Melissa Casillas,
New Mexico State Police want to hear from you. There is a reward available for information. You can reach them at
505-425-6771. And that goes for Melissa, too. If she's out there. Camera Ashley, check your texts.
Marilyn, you sent me more Get the [ __ ] out of here. No, I'm Jared, I got >> [laughter]
>> a lot. Jared, and that's how it basically went after we were done recording. You what?
It's a jumble. I'm confused. >> [laughter] >> We have a This has been like basically
me the whole me. I don't really understand all this. I don't even start to understand it.
Oh my god. Is this related to Melissa Casillas? Yes. Yes. Of course it is. Oh, no.

On June 26, 2025, 48-year-old Melissa Casias vanished from her home in Taos County, New Mexico. Her car was in the driveway. Her keys, wallet, and phones were left behind. And those phones were completely wiped and appeared to have been factory reset. Nothing about it makes sense.

In this episode, Ashley Flowers and Brit Prawat dive into a case sent in by a Crime Junkie listener, one that quickly spiraled into conflicting timelines, divided families, and a mystery that only deepens the more you look at it. They explore Melissa Casias’ last confirmed movements on June 26, 2025 in Taos, New Mexico, the surveillance footage showing her walking alone along Highway 518, why her phones and cloud data were erased just before she disappeared, the conflicting theories from her husband, Mark Casias, and her extended family, and the lead involving a potential sighting near a blue Dodge truck that was never fully pursued.

Melissa’s case is especially complicated because the people closest to her can’t agree on what happened. Her husband and daughter believe she left on her own. Other family members believe she was harmed. Investigators say there’s no clear evidence pointing definitively either way.

Despite extensive searches involving ground teams, drones, and K9 units. digital forensics, and interviews across multiple leads…there has been no confirmed sighting of Melissa Casias since that day.

This case raises difficult questions: Did Melissa plan to disappear? Was she meeting someone that day? Or is there a critical piece of evidence that’s been overlooked?

Follow Crime Junkie: Instagram: https://www.instagram.com/crimejunkiepodcast Facebook: https://www.facebook.com/CrimeJunkiePodcast/ Twitter: https://twitter.com/CrimeJunkiePod Crime Junkie is created and hosted by Ashley Flowers.

About Ashley Flowers Ashley Flowers is the top female podcaster in the U.S. and the host of Crime Junkie, the #1 podcast among women and the #1 true crime podcast globally. As the Founder of Audiochuck, she has built a top-tier podcast production company that has garnered over 2.6 billion downloads, captivating audiences with its gripping storytelling through 10+ chart topping podcasts. Ashley and her team are dedicated to creating responsible true crime content that respects victims and their families.

Follow Ashley: Instagram: https://www.instagram.com/ASHLEYFLOWERS/ Twitter: https://twitter.com/ash_flowers TikTok: https://www.tiktok.com/@ashleyflowerscrimejunkie Facebook: https://www.facebook.com/ashleyflowers.af/

Check out these other great crime channels: @annieelise FedEx Driver Planned Her Abduction and Murder | Athena Strand https://www.youtube.com/watch?v=ozXLY04SahA&t=1s @kallmekris She Was Held Captive By A Serial Killer | Kala Brown https://www.youtube.com/watch?v=QFv74NQXtAQ @bellafiori The Bizarre Case of Amy Mullis https://www.youtube.com/watch?v=6rYma3Zzw_U @rottenmangopod Influencer Hunts For Twin Lookalike On Instagram & Brutally Kills Her - But She Won't Say Why https://www.youtube.com/watch?v=Nxy84l8uQlI

Brief Summary

Melissa Casillas vanished in 2025, sparking conflicting theories about her disappearance involving family dynamics and financial struggles.

Key points

The Mysterious Disappearance. Melissa Casillas vanishes without a trace, leaving her family in turmoil.
Suspicion Falls on Mark. As the investigation unfolds, doubts about Mark's involvement begin to surface.
Blood Stain Discovery. Police find a blood stain by the fish tank, leading to further testing.
Mark's Alibi and Theories. Mark insists Melissa left on her own, despite mounting evidence to the contrary.
Surveillance Video Evidence. Mark finds video evidence of Melissa walking away, challenging the narrative of her disappearance.
Melissa Casillas: A Different Narrative. New evidence suggests Melissa was alive and well after her disappearance, challenging previous assumptions.

Episode highlights

Episode quotes

Wait, that can't be right.

Mark reacts to Sierra's account of Melissa's excuse.

8:09WatchApr 29, 2026

Tension

75/ 100High tension

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