Episode 787: The Matamoros Devil Murders (Part 1)
- May 21, 2026
- 58:34
- Full Episode
In March 1989, twenty-one-year-old Texas A&M student Mark Kilroy and some friends traveled south of the border to Matamoros, Mexico to celebrate the end of spring break, along with thousands of other American students that year. After drinking all night at a bar on the night of March 10, Kilroy got separated from his friends when they decided to call it a night a little after 2:00 am. No one would see Mark Kilroy alive again.
As one of several towns bordering the United States, Matamoros was popular with American tourists; however, by the late 1980s, it was beginning to develop a reputation for drug-related crime. In fact, Mark Kilroy was just one of sixty people who went missing in Matamoros in just the first three months of 1989 alone. When Kilroy’s friends reported him missing to the Brownsville, Texas police a massive search began, with investigators fearing Mark might have been kidnapped by one of the local gangs. It turned out, the truth was far worse than anyone had feared.
MENTIONED IN THIS EPISODE:
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References
Associated Press. 1989. "Leader in cult slayings ordered own death, two companions say." New York Times, May 8: 14.
Assocoated Press. 1989. "Hypnosis tried in hunt for student." Fot Worth Star-Telegram, March 17: 24.
Bragg, Roy. 1989. "Cult 'godfather' ordered killing." Houston Chronicle, April 13: 1.
—. 1989. "Fateful party is re-enacted." Houston Chronicle, March 25: 1.
Cartwright, Gary. 1989. "The Work of the Devil." Tecas Monthly, June 1.
Douglas, Jack, and Major Garrett. 1989. "13th victim pulled from killing field." Houston Post, April 14: 1.
Garcia, Guy. 1989. "The Believers: Cult Murders in Mexico." Rolling Stone, June 29.
Humes, Edward. 1991. Buried Secrets: A True Story of Serial Murder, Black Magic, and Drug-Running on the U.S. Border. New York, NY: Dutton.
Kreps, Mary Ann. 1989. "Machete blow reportedly killed Kilroy instantly." Houston Chronicle, April 12: 1.
Mishra, Upendra Nath. 1989. "Police search properties owned by alleged cult leader." United Press International, April 20.
Perez-Trevino, Emma. 2009. "Remebering Mark J. Kilroy." Brownsville Herald, March 8: 1.
Sanders, Kathy. 1989. "Rumors of Satanists kidnapping children have parents terrified." Fort Worth Star-Telegram, April 15: 1.
Schutze, Jim. 2023. Cauldron of Blood: The Matamoros Cult Killings. New York, NY: Open Road Media.
United Press International. 1989. "Parents of missing student seek help from state." United Press International, March 29.
Warren, Susan. 1989. "Kilroys say drug users 'to blame' for son's killing." Houston Chronicle, April 13: 1.
Cowritten by Alaina Urquhart, Ash Kelley & Dave White (Since 10/2022) Produced & Edited by Mikie Sirois (Since 2023) Research by Dave White (Since 10/2022), Alaina Urquhart & Ash Kelley Listener Correspondence & Collaboration by Debra Lally Listener Tale Video Edited by Aidan McElman (Since 6/2025) Listener Tale Theme Music licensed from https://www.purple-planet.com Main Theme: Matti Paalanen — Trick or Treat — Provided by Jamendo Ad Music: Title: Artist: BlueJay Studio — Spooky Waltz — Provided by Jamendo
Brief Summary
Mark Kilroy went missing during spring break in 1989, leading to a complex investigation involving gangs and international law enforcement.
Key points
- Mark Kilroy's Spring Break Plans. Mark and his friends plan an exciting spring break trip to South Padre Island for his 21st birthday.
- A Night in Matamoros. Mark and his friends venture into Matamoros, Mexico, for a night of bar hopping and fun.
- The Last Goodbye. As the night ends, Mark is seen talking to a girl outside the bar, but the group separates.
- The Disappearance of Mark Kilroy. Mark goes missing during spring break, leading to a frantic search by friends and family.
- Community Support. The Kilroy family receives help from local communities in their search for Mark.
- America's Most Wanted Steps In. The case is featured on America's Most Wanted, leading to unexpected rumors.
Episode highlights
- Mark Kilroy's Spring Break PlansMark and his friends plan an exciting spring break trip to South Padre Island for his 21st birthday.“This is their last trip. They got to make the most of it.”11:37May 21, 2026
- A Night in MatamorosMark and his friends venture into Matamoros, Mexico, for a night of bar hopping and fun.“They all had so much fun in Matamoros that night.”14:30May 21, 2026
- The Last GoodbyeAs the night ends, Mark is seen talking to a girl outside the bar, but the group separates.“Seeing him and getting to him were two very different things entirely.”16:30May 21, 2026
- The Disappearance of Mark KilroyMark goes missing during spring break, leading to a frantic search by friends and family.“They figured he would emerge at any second, but minutes passed and he still wasn't showing up.”17:24May 21, 2026
- Community SupportThe Kilroy family receives help from local communities in their search for Mark.“They were just absolutely wonderful how they coddled us and took care of us.”29:45May 21, 2026
- America's Most Wanted Steps InThe case is featured on America's Most Wanted, leading to unexpected rumors.“He's dead, you know. They found him shot in the head.”32:29May 21, 2026
- Break in the CaseJust as hope wanes, a breakthrough occurs in Mark's disappearance investigation.“Now just as everybody was starting to lose hope... there was a break in the case.”34:21May 21, 2026
- The Hernandez Family's DownfallThe Hernandez family's decline leads them to dangerous alliances with the Narco Satanists.“Without the charisma of their former leader... the Hernandez business wasn't just in danger of losing money.”36:13May 21, 2026






