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Jan. 13, 2022

"The 'Dexter' Copycat Killer" Mark Andrew Twitchell | Killer British Murder Stories Vol. 4 Feat. Bobbie Holmes

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In the fourth volume of Killer British Murder Stories, I am told the story of Mark Twitchell by Bobbie Holmes of Killer Stories Podcast.

Twitchell was convicted of first-degree murder on April 12, 2011, for the murder of Johnny Altinger.

He was handed a life sentence with a minimum term to serve of 25 years.

This case is notorious because Twitchell claims to have been inspired by fictional serial killer Dexter Morgan, the protagonist of the 'Dexter' book series and TV show.

This is the second of two collaboration episodes Bobbie and I recently recorded. To hear me tell the story of Penelope Jackson, check out Killer Stories.

You can find and support 'Killer Stories' here:

My episode on Penelope Jackson can be found here:
Apple Podcasts:

Intro music:
David John Brady - 'Throw Down the Gauntlet'

My recording equipment:
Shure SM7B Vocal Microphone:
Cloud Microphone Cloudlifter CL1:
Focusrite Scarlett Solo USB Audio Interface:
Rode PSA-1 Professional Studio Boom Arm:

Recorded using:

Edited in:
DaVinci Resolve 17

Mastered in:

Bobbie's references:
Blanco, M. (n.d.). Mark Andrew TWITCHELL. Murderpedia. Retrieved January 10, 2022, from

MARK TWITCHELL. (n.d.). Edmonton Journal. Retrieved January 10, 2022, from

Mark Twitchell. (2022, January 6). Wikipedia. Retrieved January 10, 2022, from

Mark Twitchell: A closer look at the evidence. (2012, July 10). CBS News. Retrieved January 10, 2022, from

Naves, A. W. (2021, June 19). The Murder of Johnny Altinger. Medium. Retrieved January 10, 2022, from

Paradis, D. (2018, August 8). The Dexter Killer. Canadian True Crime. Retrieved January 10, 2022, from

Stevenson, S. (2017, January 9). “Dexter killer” Mark Twitchell among members of dating site for inmates. CBC News. Retrieved January 10, 2022, from

Who is Mark Twitchell? Everything You Need to Know. (n.d.). The Famous People. Retrieved January 10, 2022, from

Bobbie HolmesProfile Photo

Bobbie Holmes

Podcast Host

Bobbie hosts 'Killer Stories', an independent true crime podcast.