Solved: The Dexter Killer (2008)

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If you were obsessed with the Netflix Series “Dexter” then you will love this next case, based out of Edmonton, Canada, this how Mark Twitchell was named “The Dexter Killer.”

Mark Twitchell was a married film maker, amateur from Edmonton, Canada. He had an 8-month-old daughter. He was in the process of finding a low budge tribute film to Star Wars titled “Secrets of the Rebellion.”

On October 10th, 2008, 38-year-old Johnny Altinger, told his friends that he was going to meet “Jen”, a woman he had been chatting with on the famous online dating website, PlentyofFish. Within days of him going to meet this woman, his friends started to receive weird emails form him in which he explained that he had met this woman and has fell madly in love with her and shew as taking him on a vacation to Costa Rica. Well, that is weird…. why would he be saying this? How amazing was this woman? I mean, she had to have been amazing for him to fall that fast right? And for her to be taking him on this crazy vacation so fast what did she do to make him fall in love with her?

Well, his friends found this very bizarre as they knew Johnny, this was not like him to just run away with a woman he had only known for a brief period of time. So, like any good friends that were concerned about their friend, they decided that they were going to break into his house and see what was going on.

When they got into the house, and they started to search around to see if there was any clues on who this woman was, well their worse fears were coming true. Like anytime you travel, especially if you are going to Costa Rica, you will need a passport, well, the friends found Johnny’s in his house, so he could not travel to Costa Rica without one so where was he?

Well, the person who Johnny believed he was talking to, Jen, was not a woman, it was Mark Twitchell, he had just recently shot a short film with several of his friends called, “House of Cards,”, the movie was about a man who was lured from an internet dating website to a garage where a killer was waiting. Once inside the garage, the victim would be attacked by a sadistic killer that binds him to a table and murders him with a butcher knife. Well. If you are not familiarized with the show “Dexter”, this is exactly who this goes, except, the show is with a man who works for the Police department as a forensic analyst and when somebody gets murder and he finds out who they are, he takes them to his little hide outs that he has and tortures and kills them, after that he gets on his boat and takes them to burial ground and dumps the bodies.

So, this Mark Twitchell, his film was pretty much a practice run for a real murder with Johnny Altinger as the victim and Mark Twitchell as the killer. What is even more crazy just a week before the murder, Twitchell had lured another man to the garage by pretending to be a woman, his name was Gilles Tetreault, but when he arrived at the garage, Twitchell came at him with a stun baton. Tetreault found back and managed to escape. Tetreault later explained that he did not go to the police because Twitchell had threatened to him if he did.

When Johnny arrived at the address provided by “Jen,” he received a text message telling him to come into the garage where she would be. Well, that is not crazy at all, why would she be waiting in a garage and not in the house that would have been my first concern and I would have been questioning it. It was the very same garage that Twitchell rented for the movie he had shot earlier. It was setup like a kill room. There is another fact on the show. And another fact was that that exact show, “Dexter,” was Twitchell’s all-time favorite.

Once Altinger was inside, Twitchell ambushed him with a knife and a heavy pipe. He beat Altinger within an inch of his life and then stabbed him to death. Once dead, Twitchell then dismembered him and attempted to burn his remains, well it was unsuccessful, so he decided he was going dump his arms, legs, and organs in a near by sewer drain.

After the murder, Twitchell sat down at his laptop and wrote a new story, and it goes: “This story is based on true events. The names and events were altered slightly to protect the guilty. This is the story of my progression into becoming a serial killer.”

Police did not have a hard time tracking down Twitchell. Altinger was smart and had sent an email to a friend on the day he disappeared with directions to “Jen’s” House. How freaking smart is that!

Twitchell was quickly apprehended and interrogated. He Told authorities that he had no idea who Jen or Altinger were. What a liar…he knew exactly. However, when police confiscated his laptop what they had found made everybody in the department extremely uncomfortable. They discovered the dark, violent, and twisted story that Twitchell had started to write following the murder of Altinger.

The story was supposed to be fiction but Twitchell wrote in detail about the death of Altinger and dumbly expressed that he was planning on killing a new victim each Friday.

He describes in great gory details how he played with Altinger’s severed head, he states in his story: “I grabbed his jaw with my gloved hand and moved it while making a funny voice to make it look like it was talking and laughed to myself at the total silliness of it all.” This is very disturbing. I got chills when I was doing my research on this and read that. For somebody to play with a severed head like it was alive.

When police conducted a search of Twitchell’s car, they found not only Altinger’s DNA but as well as a yellow sticky note that reminded him to clean the “Kill Room” and then to go have sex with a woman who was not his wife. That is right, his wife, what did she think he was doing while all this was going on? What did she think when he was arrested for murder?

Police also discovered a novel about Dexter, the fictional character from the show I described earlier. A search of Twitchell’s Facebook profile showed that he was obsessed with Dexter and even referred to himself as “Dexter.” How weird to have that kind of obsession.

During the trail, Twitchell finally confessed to killing Altinger but also claimed that he did it in self-defense. He claimed that he had lured Altinger to the garage of telling him it was all a joke, hoping that he would write about it on the internet and create such a big buzz about it for his short film. He stated that Altinger “did not seem humored at it” and got into a physical fight before Twitchell grabbed a pipe and smashed him in the forehead. He said he then reached for the knife and stabbed Altinger to protect himself.

Of course, the prosecution refuted his claim of self defense and contended that Twitchell had lured Altinger to the garage that night for only one reason, to kill him in a way that would match the movie he had made just weeks before.

After a month of testimony and evidence, the jury only deliberated for 5 hours. 5 hours is nothing! They found Mark Twitchell guilty of first-degree murder which carries an automatic life sentence without the possibility of parole for a minimum of 25 years.

When the actor who plays “Dexter” on the Netflix series, was informed of Twitchell’s obsession he stated, “it was troubling thin to consider.” He also stated, “I don’t think it is a primer on serial killing or it advocates the lifestyle. I would hope that people’s appreciation was more than some sort of fetish with the kill scenes.”

The writer of Dexter also commented on the Twitchell’s fetish with the show and noted, “Reading Dexter will not make you a killer. If you are not already capable of killing another human being in a cold, cruel, deliberate way, no book ever written will make you capable of doing so. There are no magic words that will turn you into a psychopath.”

I do have to agree with the writer though, a book will not turn you into a killer, you already must have that implanted in your brain or you are “wired” that way. I mean, I guess a book or show could make you have a psychotic break and brings those out if you were hiding them but turning a normal human being into a killer with no previous history of violence, no I do not see that happening.


The Dexter Killer – Mark Twitchell • Morbidology

Mark Twitchell – Wikipedia

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