Mark Andrew Twitchell was born in Edmonton on July 4, 1979. He made short science fiction films, ran a small production company, and was an enthusiastic member of the local Star Wars fan scene. He was also a fantasist about money and about himself, and he was deeply preoccupied with the American television series Dexter, about a forensic technician who is a serial killer.
In October 2008 he rented a garage in south Edmonton, kitted it out with plastic sheeting and restraints, and shot part of a short film there about a man who lures victims through internet dating. He then did it. The Canadian press called him the Dexter Killer, after the television series he had modelled the killing on.
On October 3, using a fake profile of a woman named Sheena, he arranged for Gilles Tetreault to come to the garage. Twitchell attacked him in a hockey mask with a stun baton; Tetreault fought free and escaped, and did not report it, being ashamed of having gone to meet a stranger. On October 10 he lured Johnny Altinger, a thirty-eight-year-old pipeline worker, the same way, killed him, dismembered the body and put it into a sewer. He then sent messages from Altinger's accounts saying he had gone to Costa Rica with a woman.
Altinger's friends did not believe it and went to the police, and Tetreault came forward when he heard. On Twitchell's laptop was a deleted eleven-thousand-word document beginning with the line that the story was based on true events, headed SKConfessions, describing both attacks in the first person.
He was convicted of first degree murder at Edmonton on April 12, 2011, and given life with no parole for twenty-five years. The document was read to the jury. His defence, that the killing had been self-defence and the document fiction, took twelve hours to reject.