After his parents divorce at age 7, Monteith and older brother Shaun are raised by his single mother, Ann McGregor, in Calgary, Canada. Dropping out of school in the ninth grade, he works part-time jobs and plays drums in a local band until meeting casting director Maureen Webb. "It didn't even occur to me what actors did," Monteith later tells the Times Colonist. "Three weeks later I moved to Vancouver with just a bag of T-shirts and two pairs of pants."
Monteith makes his onscreen debut in a 2004 episode of Stargate: Atlantis, and goes on to guest-star on Kyle XY, Kaya and Fear Itself (right). "I call myself a working-class actor," he later tells The Toronto Star. "You know, you go from one one-line gig to the next one-line gig, to a couple of episodes on this show, a couple of episodes on that show, to a small part in a movie...I was making a good living. But it really wasn't a life."
After sending producers a tape of himself playing "Tupperware drums," Monteith lands the role of jock-turned-crooner Finn Hudson on Glee. "It was such a long shot, such a Hail Mary," he tells the Times Colonist. "I still feel like they've made a mistake and some day they're going to realize I'm the wrong guy for the job." After debuting in the spring, Glee premieres September 9.
With Glee's music racing up the Billboard charts and the show's popularity rising, Monteith and costars Lea Michele and Matthew Morrison land the cover of EW. "I keep getting e-mails and phone calls and running into people at parties just telling me the show makes them feel happy," co-creator Brad Falchuck tells the mag. In November, Monteith joins Morrison and costar Mark Salling on PEOPLE's Sexiest Man Alive list.
After being snapped together at a pre-Grammys party in January, Monteith and country queen Taylor Swift are spotted looking cozy at a Studio City, Calif., bowling alley. But in May, the actor downplays the relationship, telling Ellen DeGeneres, "We're just friends. I don't know where the time is to date these days."
Monteith and Glee costar Lea Michele go public with their relationship during an NHL game in New York. Days later, the new couple continue to spread their affections for one another publicly in the Big Apple, with Michele going as far as referring to Monteith as "really hot" on her Twitter account.
While shooting Glee's fourth season, Monteith announces he "has voluntarily admitted himself to a treatment facility for substance addiction," his rep tells PEOPLE exclusively. The actor, 30, struggled with substance abuse in the past, admitting in a 2011 interview that he had previously entered rehab at 19. Offering words of support, girlfriend and costar Lea Michele tells PEOPLE, "I love and support Cory and will stand by him through this. I am grateful and proud he made this decision." Less than a month later, Monteith completes treatment, and reunites with Michele.
Monteith is found dead after failing to check out of his room at the Fairmont Pacific Rim Hotel in Vancouver, Canada. Police report that the actor had been out with friends the night before, but returned to his room alone, where he was believed to have died hours before he was found. "We are in shock and mourning this tragic loss," his rep says in a statement, while members of Hollywood – from Glee costar Dot-Marie Jones to rumored ex-girlfriend Taylor Swift – express their grief over Twitter.
Following an autopsy and toxicology tests, a coroner reveals Monteith died from a lethal combination of heroin and alcohol. His body is cremated on July 17 during a private ceremony attended by most of his family and Michele, whose rep issues a statement, saying the actress is "deeply grateful for all the love and support she's received from family, friends, and fans," and that she is grieving alongside the star's family.
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