A Promise to Helene

Dateline NBC

  • Sep 1, 2026
  • 40:32
  • Full Episode
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<p>When 21-year-old college student Helene Pruszynski is found murdered, the case remains cold for nearly forty years until a new detective uses an innovative method to catch Helene’s killer. Josh Mankiewicz reports.</p><br/> <p>Hosted by Simplecast, an AdsWizz company. See <a href="https://pcm.adswizz.com">pcm.adswizz.com</a> for information about our collection and use of personal data for advertising.</p>

Brief Summary

Helene Pruszynski's cold case is solved after 40 years through DNA evidence and a detective's persistence.

Key points

  • A 40-Year Mission. A cold case mystery unfolds as a friend vows to find Helene's killer after decades.
  • The Disappearance. Helene Pruszynski vanishes after leaving work, sparking a frantic search.
  • The Chilling Confession. Two serial killers confess to Helene's murder, but inconsistencies arise.
  • DNA Evidence Breakthrough. New DNA technology offers hope in solving Helene's cold case after decades.
  • Detective's Determination. Detective Jensen pursues leads through genealogy to find Helene's killer.
  • The DNA Match. A cousin's DNA leads investigators closer to the killer, revealing a family connection.

Tension

85/ 100High tension

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