Peter Woodcock was born in Peterborough, Ontario, in 1939. From the beginning, his life was filled with challenges. His mother was a young woman who couldn't take care of him, so he was placed in foster care. Unfortunately, his early years in foster care were unstable and he was moved around frequently.

Peter struggled to fit in with other children and often felt isolated. By the age of five, he was showing signs of serious emotional and behavioral issues. He was described as a very difficult child to manage, often throwing tantrums and acting out aggressively.

At the age of seven, Peter was sent to the Protestant Children's Home. There, he continued to struggle with making friends and fitting in. His odd behaviors and difficulty in social interactions made him a target for bullying. The constant bullying further isolated him, and he began to develop a fascination with trains and maps, often retreating into his own world.

As Peter grew older, his behavioral problems worsened. He was eventually placed in a special school for emotionally disturbed children. Even with this specialized attention, he continued to exhibit troubling behaviors. He had a hard time understanding social norms and would often make inappropriate comments or actions.

By the time he reached his teenage years, Peter's fascination with violence began to emerge more clearly. He would fantasize about hurting others and started acting on these thoughts by torturing and killing small animals. Despite these clear warning signs, he did not receive the intensive psychological help he needed.

Peter Woodcock's favorite possession was a red and white Schwinn bicycle. He loved riding it all over Toronto, even during the cold winters. He created a fantasy world where he led a gang of 500 invisible boys on bikes called the 'Winchester Heights Gang.' His foster parents knew about his wandering and fantasies but didn't know he was riding his bike around Toronto and sexually assaulting children.

On September 15, 1956, 17-year-old Woodcock was riding his bike around Exhibition Place when he met 7-year-old Wayne Mallette. He lured Wayne out of sight and strangled him to death. Wayne's body was found the next day, with his clothes removed and then redressed. His face was pushed into the dirt, and he had two bite marks, one on his calf and another on his buttock. There was no evidence of rape, but pennies were found near his body, and Woodcock had defecated next to him.

The Toronto Police initially arrested and interrogated another boy, Ron Moffatt. Despite witnesses placing Ron in a movie theater before and after the murder, he was found guilty and sentenced to youth detention. Eventually, police realized there was a serial predator in Toronto, but Ron was not released until Woodcock was arrested and convicted. Woodcock later confessed, and Ron was released in 1957.

On October 6, 1956, Woodcock met 9-year-old Gary Morris while riding his bike around Cabbagetown. He took Gary to Cherry Beach, where he strangled and beat him to death. The coroner found that Gary died from a ruptured liver. His body had a bite mark on the throat, and paper clips were scattered nearby. His clothes were removed and redressed.

On January 19, 1957, Woodcock approached 4-year-old Carole Voyce while riding his bike and offered her a ride. He took her under the Bloor Viaduct and murdered her. Her clothes were pulled off, and she appeared to have been choked and sexually molested. A tree branch had been forcibly inserted into her body.

Witnesses saw a teenager cycling away from Carole Voyce's crime scene, leading to an accurate composite sketch published on the front page of the Toronto Star. This led to Woodcock's arrest on January 21, 1957. He confessed to all three murders and was most afraid of his mother finding out.

Woodcock was tried for the murder of Carole Voyce. On April 11, 1957, he was found not guilty by reason of insanity and was sent to the Oak Ridge division of the maximum-security Penetanguishene Mental Health Centre. While imprisoned, he was diagnosed as a psychopath and underwent various psychiatric treatments, including LSD therapy and other personality-breaking drugs. He engaged in coercive sexual acts with fellow inmates and created imaginary stories to manipulate them.

Eventually, Woodcock was transferred to less-restrictive institutions and arrived at the Brockville Psychiatric Hospital. There, he changed his name to David Michael Krueger and reconnected with Bruce Hamill, an Ottawa killer. Krueger convinced Hamill that an alien brotherhood would solve his problems if he helped kill another inmate, Dennis Kerr.

On July 13, 1991, Hamill bought weapons and met Krueger at the Brockville hospital. They signed Krueger out on his first publicly escorted day pass. They arranged to meet Dennis Kerr in the woods, where they attacked him, mutilated his body, and sodomized the corpse. Krueger then walked to a police station and turned himself in.

For the murder of Dennis Kerr, Krueger was sent back to the Oak Ridge division of the Penetanguishene Mental Health Centre. He spent the rest of his life there and was the subject of a biography and several documentaries. On March 5, 2010, his 71st birthday, Krueger died of natural causes.