Michael Wayne McGray was born on July 11, 1965, in Collingwood, Ontario. He spent his early years in Argyle, Nova Scotia.

On May 1, 1985, Michael Wayne McGray murdered 17-year-old hitchhiker Elizabeth Gale Tucker in a wooded area near Weymouth, Nova Scotia. Her body was discovered on October 6, 1985, by a hunter. In connection with her murder, a man named Gregory George Ashford was questioned but not charged.

On November 14, 1987, McGray, along with two accomplices, robbed a taxi driver in Saint John, New Brunswick. During the incident, one of his accomplices, Mark Gibbons, was found dead shortly after the robbery. Although Warren, another accomplice, was charged with Gibbons' murder, he was found not guilty. McGray received a five-year prison sentence for the robbery.

In 1991, while still in prison, McGray was given a weekend pass to a halfway house. During this time, he murdered Robert Assaly on March 30, 1991, by stabbing him multiple times in his apartment. The next day, he met Gaetan Ethier and killed him as well. After these murders, McGray did not return to prison and was not captured until May 1991.

On February 28, 1998, Joan Hicks and her 11-year-old daughter, Nina, were murdered in their Moncton apartment. McGray was identified as the murderer by a witness and was arrested the following day. After his arrest, he confessed to the murders of Assaly and Ethier.

McGray's confessions continued as he claimed responsibility for the 1985 disappearance of Kimberly Amero, saying he killed her and buried her in a specific area. However, searches turned up no evidence.

On March 20, 2000, McGray pled guilty to the murder of Joan Hicks. He later claimed to have killed 11 other people across Canada and even the United States. In May 2001, he was charged with the murder of Elizabeth Gale Tucker, which had remained unsolved for years.

In November 2010, McGray killed his cellmate, Jeremy Phillips, at a medium-security prison. He claimed that Phillips had set up a false scenario, but others doubted his explanation.

On July 12, 2019, McGray was named as the prime suspect in the 1995 murder of Brenda Way in Dartmouth, Nova Scotia, which had previously led to the wrongful conviction of her boyfriend.