The popularity of the American TV Series ‘Dexter’ featuring the sinister Dexter Morgan, a forensic blood spatter analyst by day and serial killer seeking justice against criminals who have evaded the law by night, has resonated a little too closely for some. The concept of murder as an act of justice, a prepared and carefully controlled ‘kill room’ and dismemberment of the body to hide the evidence, undeniably made for a captivating crime drama.

The final series of Dexter drew mixed reviews from dedicated fans but the Showtime network reported the series had an average of 6.4 million weekly viewers. Almost all those who watch shows like Dexter are simply entertained and absorbed by dark crime TV with intense characters and an ongoing storyline. For a handful, however, their fascination became a fantasy that then spilled over into real life.


Forensic Psychologist Dr. Katherine Ramsland wrote on her Shadow Boxing blog on Psychology Today on the number of killers who have been inspired by the Dexter show. In America in 2009, 17-year-old Andrew Conley strangled his 10-year-old brother to death before wrapping two plastic bags around his head copying his admired Dexter. He received a life sentence in prison.

In Norway in 2010, Havard Nyflot watched back to back episodes of the hit series and decided Shamrez Khan, a man who had approached him to kidnap and torture a woman who had rejected him, deserved to die for his corrupt plans. Attempting to follow the steps he had closely observed Dexter carry out in each episode, Nyflot made a disastrous plan that ended in the murder of the woman and placed himself and his intended target on trial for first-degree murder, receiving a sentence of 17 years in prison. In Britain in 2016, 21-year-old Mark Howe stabbed his mother over 50 times inside their home and was described as being ‘obsessed with Dexter’.

One man who took his obsession and admiration for the Dexter character a step further is Canada’s 31-year-old Mark Twitchell. In October 2008 in the city of Edmonton in Alberta, Twitchell lured a man to his death using a fake online dating profile, violently killing him and cutting up his body in a rented garage he had transformed into his own ‘kill room’.

Mark Twitchell

Mark Twitchell

Mark Twitchell was an amateur filmmaker determined to make it big. He dreamed of big budgets, producers and fame confident that his scripts, casting and camera skills were enough to break into the entertainment industry.

John Brian ‘Johnny’ Altinger was 38-years-old, lived in Edmonton, and was a member of the dating website Plenty of Fish. In early October 2008, he began talking to a ‘woman’ via the website and accepted an invitation to meet her on 10 October. He was given directions to a garage in south Edmonton, calling his friend Dale Smith excitedly to let him know his plans. Smith received a second call from Altinger that night, telling him the woman was not in the garage but a man was who told him he was a filmmaker. Altinger was going back to the garage believing the woman he was due to meet would now be there.

The next his friend heard from him was an email that told him he was going away with this woman called Jen and would not be back from some time. Suspicious of the language used which did not match the emails Altinger usually sent, friends went to his home and discovered no indications of a planned period away and his passport still in his apartment. Concerned for their friend, they informed the Edmonton Police Service who launched a missing person investigation.

John Altinger’s last known location was the garage lock-up and Dale Smith was able to repeat the directions Altinger had told him for police to locate the garage themselves. The name on the rental agreement for that garage was Mark Twitchell.

The rented garage was used by Twitchell two weeks before the murder to shoot an eight-minute horror film he called ‘House of Cards’. The plot was eerily similar to the fate of John Altinger in the same location just weeks later. The film was used as evidence in his murder trial, depicting his planning of what he would do and the similarities to Showtime’s Dexter were also noted. Detective Anstey who worked on the case told the Globe and Mail, “We have a lot of information that suggests he definitely idolizes Dexter, and a lot of information that he tried to emulate him during this incident.”

Mark Twitchell's rented garage

Mark Twitchell’s rented garage

Charged with first-degree murder, Twitchell told a strange tale at his trial. He pleaded not guilty to murder yet admitted to the court, according to the Globe and Mail, that he did lure John Altinger into the rented garage, stab him to death and cut up his body for disposal. He went on to tell the court that his actions came after filming his movie with two friends in the same garage weeks earlier. The movie featured a cheating husband lured to a garage location by thinking he was meeting a woman from a dating website. Once he arrived, however, he was attacked and killed by a man wearing a mask in payment for his cheating behaviour.

Twitchell told the court he came up with the idea of actually mimicking the plot in real life but not killing the individual in an attempt to provide publicity for his film. Once the film was released he said, and those people who had lived through the same experience saw it, they would talk about it and create a ‘buzz’. He said he had killed Altinger in self-defence when they began fighting after Altinger ‘did not react the way he expected’ when he was told Twitchell was a filmmaker and wanted Altinger to write about his experience on the web. He said he panicked, dismembered Altinger’s body, and got rid of it in a sewer. He then went to Altinger’s home and logging in using auto-saved usernames and passwords, sent the emails to his friends to delay the time before anyone realised he was missing.

Blood evidence found inside the garage

Blood evidence found inside the garage where John Altinger was murdered.

Aside from the blood evidence inside the garage, the most damning evidence against Mark Twitchell was the extensive and detailed ‘kill diary’ forensic experts found deleted on his laptop. In over 40 pages of descriptive text he had entitled ‘SKConfessions’, he began with the line: “This is the story of my progression into becoming a serial killer.” Discovered after his arrest, it stated: “This story is based on true events.”

CBC Canada reported the document read like a diary and the events it so graphically described mirrored the actions police believe were taken by Mark Twitchell in the planning and execution of John Altinger’s murder. In the days leading to Altinger’s murder, Twitchell purchased knives, plastic sheeting, saw blades, and a meat cleaver.

“I felt stronger, somehow above other people. I felt like the proud owner of a very dark secret that no one would ever be in on.”

The document details the online dating website scam to lure in an unsuspecting victim. It chronicles the first failed attempt where after getting his victim into the garage; he unsuspectedly fought back and escaped matching the actual events that took place with Gilles Tetreault, who has now published a book entitled “The One That Got Away” about his experience. The remainder of the document details his second victim and how this time he bludgeoned him with a pipe and stabbed him multiple times before dismembering the body and putting the body parts into garbage bags and dumping them in a local sewer.

In June 2010, almost two years after his arrest while still awaiting trial, Twitchell gave police a hand-drawn map highlighting the location he had disposed of John Altinger’s remains.

Mark Twitchell was found guilty of first-degree murder and sentenced to life in prison on 12 April 2011. Another document found on Twitchell’s laptop did not make its way into the evidence file for the jury to read during his trial.  Entitled “A Profile of a Psychopath” and believed by investigators to have been written by Twitchell, it is a detailed self-analysis of personality and behaviour. CBC Canada reported the day Twitchell was found guilty that the author had written, “As a producer I can profit from the sale and distribution of my work. But as a serial killer I would get nothing more than a quick rush of adrenalin and a prison sentence to follow.”

The case of Mark Twitchell was as bizarre as it was gruesome. John Altinger lost his life to a violent man who lived in a world of fantasy, creating an elaborate plan to kill in order to meet the twisted desire he had to feel powerful and like he was someone. What he achieved was taking the life of an innocent man and a lifetime prison sentence.