“I’m a huge walking oxymoron,” Chris Zylka, one of the stars of HBO’s buzzy new sci-fi series The Leftovers, tells me. “People think they’re going to get something that’s a lot different from what they get.”

Coming from a Hollywood stud on the verge of his biggest break, it’s a self-assessment that too easily could come off as pompous or groan-inducing. But spend an afternoon with the 29-year-old actor, have him talk you through his 17 arm tattoos, and hear his can’t-make-this-stuff-up backstory, and the statement plays as earnestly as he delivers it.

Because you are expecting something when you meet Chris Zylka.

His star has steadily been on the rise in Hollywood since landing his first guest spot on The CW’s 90210 reboot in 2008. Owed to his all-American good looks and contagious affableness, he parlayed the guest stint into steady work on a rotating carousel of slight TV series targeted at the tween demographic: Disney’s Hannah Montana, ABC Family’s 10 Things I Hate About You, The CW’s The Secret Circle. His film career consisted largely of genre exploitation flicks, like Piranha 3DD and Shark Night 3D, before he landed a plumb role as the resident high school bully opposite Andrew Garfield in The Amazing Spider-Man.

Combine that resume with its corresponding rabid attention from the tween fanbase and his stint as a model for Abercrombie and Fitch, and you might expect Zylka to be a little vapid. Too clean-cut for his good. And, above all of that, boring.

But he’s right. What people do get from him far exceeds those expectations they have, providing a clearer indication at the complexity required to be cast in The Leftovers, a series co-created by Lost’s Damon Lindelof and executive produced by Friday Night Lights’ Peter Berg. It takes place in the aftermath of a global “Rapture” of sorts, in which 2 percent of the world’s population vanishes and those left behind are forced to grapple with the loss.

Zylka plays Tom, a tortured college-aged kid who, following the events, estranges himself from his father (Justin Theroux) to follow a cult-leader-like prophet. That scene in all of the show’s trailers, with the young guy swimming underwater and screaming in anguish? That’s Tom.

Getting cast in the role is the end of the story of how Chris Zylka became one of Hollywood’s most exciting actors to watch. The beginning of it, though, is far more interesting.

Zylka grew up in Ohio, with the last name of Settlemire. He changed it to his mother maiden’s name Zylka after dropping out of the University of Toledo, where he studied art and played football for two years. During his second bowl game, his grandfather had a heart attack, and he left to help care for him.

“I changed it for my grandpa,” Zylka says. “I wanted to make him proud.” Before he did, he asked his great-grandmother for permission. “Before she passed away, she got to see it in the title sequence for 90210.”

Zylka was never had ambitions of acting growing up, preferring instead to play football and tag graffiti. “I was always the misfit jock who was with people painting on walls,” he says. But during his time caring for his grandfather, he was taught by the elder Zylka about Russian art and the Stanislavsky method. “Growing up in Ohio, you don’t really look at acting as art at all,” he says. “My grandfather opened my eyes to all this new stuff. I was like, ‘Cool, I want to try out all that.’ So I moved to L.A.”

The one thing he forgot, though, was a plan.

He arrived in L.A. with nowhere to go, no job, no money, and no contingency. As such, he ended up homeless. He lived in the parking lot of a 7-Eleven in Burbank, filling the mondo-sized Army surplus bag he brought with him with hoodies to use as a pillow while he slept behind the dumpster. In the mornings, he would travel to a nearby apartment complex called The Promenade, where he would jump over the fence, use their gym, shower, and charge his phone—“so my mom didn’t know I was homeless.”

He eventually found a string of restaurant jobs, and began couch surfing with friends he made at them. How he first broke into the business is another of those TV-movie-ready stories: Zylka was literally discovered at a restaurant.

His first manager, Jon Simmons, happened to be there while Zylka stopped by to pick up his paycheck—he was working there at the time. Simmons had just gotten rid of a client who looked a lot like Zylka and asked him if he was an actor. “I was like, no, but I want to be,” Zylka remembers. “It’s wild, right? I was just going to get a paycheck at a fucking bar!”

Steady work on the tween-show circuit (Hannah Montana, 90210, Secret Circle) followed, but two film roles were integral in altering how Hollywood looked at Zylka. Obviously, being cast as Flash Thompson in The Amazing Spider-Man and given that hilarious basketball scene with Andrew Garfield was a big freaking deal. “That’s the first time I called my mom and cried,” he says.

But his performance in 2010’s indie sci-fi sex odyssey Kaboom may have been the first time the industry saw him as an adult. To begin with, Zylka was naked a lot in the movie. That helped.

(To boot, Zylka’s big scene at the end of The Leftovers pilot is performed fully nude, while skinny dipping. “I think it makes the crew more uncomfortable than it makes me,” Zylka says about shooting nude scenes. “I mean I don’t shower with shorts on. I don’t recall ever jacking off with underwear on. So the nudity makes it real, I guess.”)

But beyond the fact that his ass is now Google-able, the film’s big Cannes Film Festival debut introduced Zylka as an actor, more than just a cute CW star. Naturally, as is typical in Zylka’s life, Kaboom’s red carpet premiere didn’t go off without giving him yet another cocktail party story.

“At the time I couldn’t afford a bow tie, and in France they take that seriously,” Zylka says. Cannes’ muscle men were barring him from the red carpet for his own premiere because he wasn’t properly dressed in a tuxedo with a bow tie, “so one of the producers had to take off his bow tie and give it to me.”

It’s after that story that Zylka starts waxing on about how he has to pinch himself and savor this moment in his career, given what it’s taken to get there. It’s the kind of talk that one would expect to come off as artificially humble, or that would typically be insufferable coming from an incredibly attractive, successful actor. But there’s something about Zylka’s genuineness, and certainly many things about his story, that defies those expectations, once again.

“I’m so proud of this, of being on this show,” he says about his big HBO gig. “It’s the first thing I’m a major part of that is something I can be like, ‘Dude, look what I’m on.’ I’ll sit at home alone or be in the shower and think, ‘God, five years ago I was on Hannah Montana. Now I’m on a HBO show. Holy shit.’ Instead of putting pressure on myself, I just get excited.”