Crime Chats

episode artwork

Lisa Iacoletti & Hilary Morrow

04 August 2026

59m 53s

Mark Twitchell: The Dexter Killer

00:00

59:53

In October 2008, aspiring filmmaker Mark Twitchell lured a stranger into a garage using a fake online dating profile. What happened next was far more disturbing than anyone expected.

Inspired by his obsession with movies, storytelling, and the TV show, Dexter, Twitchell attempted to create his own real-life “crime story.” Investigators quickly uncovered that his carefully planned fantasy had become a horrifying reality.

⚠️ Listener Discretion: This episode contains discussions of murder, violence, and disturbing crime scene details.

🔎 What We Cover

  • Johnny Altinger's background and how he met "Jen"
  • Johnny's disappearance and the investigation that followed
  • Mark Twitchell's police interviews, interrogations, and the evidence found
  • Twitchell's arrest and time behind bars
  • The first-degree murder trial
  • The letters sent back and forth between Twitchell and the reporter writing a book about him
  • The problems with the Canadian prison system

💬 Crime Chats Discussion

Do you think violent offenders should be free to lead full social lives while behind bars for their horrific acts? Is the Canadian prison system too lenient?

Let us know your thoughts.

📚 Sources

Amato, A. (2026, March 18). Family contact already met, victim's family trauma reasoning in Twitchell leave denial. CTV News Edmonton. https://www.ctvnews.ca/edmonton/article/family-contact-already-met-victims-family-trauma-reasoning-in-twitchell-leave-denial/

Bennett, D. (2011, April 12). Accused killer Twitchell played with victim's skull: court document. Global News. https://globalnews.ca/news/114056/accused-killer-twitchell-played-with-victims-skull-court-document/

CBS News. (2024, August 14). "The Dexter Killer:" Inside the mind of a murderer. https://www.cbsnews.com/pictures/mark-twitchell-the-dexter-killer-evidence-photos/

Cinematic Psychopathy: A Forensic and Criminological Analysis of the Mark Twitchell Case. (n.d.). [Forensic Analysis Report].

Venditti, A. (2024, August 18). Inside the mind of Mark Twitchell, "The Dexter Killer". CBS News. https://www.cbsnews.com/news/mark-twitchell-the-dexter-killer-48-hours/

Wikipedia contributors. (2026, July 10). Mark Twitchell. Wikipedia, The Free Encyclopedia. https://en.wikipedia.org/wiki/Mark_Twitchell

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