Cory Monteith Appreciation: First an Addict, Then a Gleeful Innocent

For years, the "Glee" star reversed the trajectory of so many troubled young stars

It's a story older than the Mickey Mouse Club: Child stars spending their youth chasing fame, only to flame out in their twenties or thirties, when both fame and their innocence are gone.

For a while, Cory Monteith's life took the opposite trajectory. He turned to acting to escape the hell of teenage addiction, and won his role on "Glee" partly because of an innocent quality he held onto even through the chaos of his early years.

See Photos: Cory Monteith: A Life and Career In Pictures

But his darkness caught up to him. He was found Saturday, dead at 31 in a Vancouver hotel room. He had completed a stint in rehab just two months earlier.

Born in Calgary, Alberta, he was raised by his mother in Victoria, British Columbia. His parents divorced when he was 7. He found drugs and alcohol by 12, and was soon in and out of schools.

In an "Inside the Actors Studio" appearance last year, he told James Lipton he had lost count of how many schools he attended. Lipton informed him that the number was 16.

"A lot of them were alternative programs," Monteith explained. "For kids that are, you know" — he made air quotes — "problematic."

Also see: 20 of Cory Monteith's Greatest 'Glee' Performances (Video)

In a Maclean's profile, he said he sometimes committed petty crimes, and slept under bridges or in tents. He worked temporary jobs, including Wal-Mart greeter, roofer, and call-center operator.

But he told Lipton he changed his life at 19, when he "moved to another city, to live with a friend of my mother's who was recovering from addictions. And I started on that route. I found something that I completely understood."

Getty ImagesHis something was acting. In his early twenties, his wholesome, athletic look helped him land roles on shows including "Stargate Atlantis," "Supernatural," and "Kyle XY."

When he won the role of Finn Hudson on "Glee" in 2009, it wasn't for his musicality. To get an audition for the show, he submitted a video of himself playing Tupperware drums with pencils. "Glee" co-creator Ryan Murphy took note, but said he was supposed to sing. Monteith obliged with a goofy video of himself performing REO Speedwagon's "Can’t Fight This Feeling."

That earned him an invitation to a cattle call, where he knew he wasn't the strongest singer. But he had what a casting agent considered more important: The ability to capture Finn's “naive, but not stupid” sweetness.

Monteith quickly came into his own as a vocalist, performing showstoppers like U2's "One" and Michael Jackson's "Man in the Mirror." As the show became an instant hit for Fox, so did Monteith's songs, which like many others on "Glee" became iTunes hits.

And Monteith became an inspiration to young people who struggled as he once had. He advocated for homeless youth, and spoke bluntly about his own addictions. And his show spoke for victims of bullying, gay teens struggling with their sexuality, kids who hadn’t yet figured out who they were.

Also read: Fans Grieve 'Glee' Star Cory Monteith Death's Across the Internet

But Monteith sometimes seemed less at ease than his co-stars. "Glee" placed him alongside the kinds of talents who seem to roll off Disney-fied assembly lines. Kevin Hale was a boy band veteran when he joined the show. Lea Michele, who would become Monteith's girlfriend, has already starred in Broadway's "Spring Awakening." (When I interviewed her about that role, in 2006, she was poised, self-assured – and 20.)

Monteith had spent the same years his colleagues had spent in recitals and rehearsals getting high, cutting classes, sleeping in parks. In March, he admitted he had relapsed, and checked into a program for help.

In June, he and Michele looked happy together at a charity ball (pictured, right). She talked about how proud she was of Monteith for getting help.

And then he died. No cause has been released.

Also read: Cory Monteith's Autopsy Scheduled for Monday

The sudden loss of one of its sweet, naïve Finn throws "Glee" into despair and uncertainty. The show will have to explain, somehow, the sudden absence of someone so young.

So will the real world.

Watch Monteith on "Inside the Actors Studio":