Behind the scenes of IFC's Kristen Stewart starrer, "Camp X-Ray," is a real-life story of redemption. That is the story of rising film and TV actor Lane Garrison, Stewart's primary antagonist in the Oct. 17 release as a Guantanamo Bay corporal who turns spiteful after being rebuffed by her newbie Army guard.

Only a few years ago, Garrison was behind bars.

"Sometimes I feel like God himself chose me to be a part of this film," says the handsome, buff, blue-eyed Dallas native. "It's very cathartic for me to play this."

In December 2006, he was responsible for a car crash, which left a teenager dead. He pled guilty to vehicular manslaughter, driving under the influence and providing alcohol to a minor and was sentenced to 3 1/2 years in jail, and wound up being released after two for good behavior. "I went to eight prisons over two years in the state of California. I've met a lot of brutal guards, a lot of men in a hostile environment who became like their environment and became desensitized — and guys who got their pleasure off of other people's pain. For so long I couldn't understand that. I just couldn't understand that," he says.

"Of course, obviously, I put myself in that situation, something I wouldn't wish on anyone and I needed to pay the consequences. But for so long I struggled with how men could treat other men that way. And this character is basically playing a prison guard at Guantanamo Bay. I think my past really allowed me to breathe life into this role, because I experienced it first hand on the other side."

Garrison says he didn't talk to "Camp X-Ray" filmmaker Peter Sattler or Stewart about his history prior to being hired for the film. Though he has been quite open about it, his film colleagues weren't aware at first. When he did tell them his story, "well, both Peter and Kristen were sort of awed by it," Garrison says.

He proved a resource for Peyman Moaadi, the New York-born Iranian actor, screenwriter, and director best known for starring in the Oscar-winning Iranian film, "A Separation." In "Camp X-Ray," Moaadi plays a Guantanamo Bay detainee who breaks through Stewart's character's military veneer and gets into her head. Garrison says his experience "allowed me to talk to Peyman about what it's like to be in a cell, what it's like to be locked away from society."

He stresses, "I'm pretty honest with everybody about it. It's something that changed my life and changed other people's lives. You know, it's something I also go around speaking about around the country. And hopefully changing some kids and even adults who've been foolish about not drinking and driving, and letting them know, this can happen to anyone if you make a foolish decision."

Garrison feels his character has become desensitized after his long stint in the prison-like environment. He is also "one of those guys who feel, 'These people are all guilty. They're all terrorists, they all deserve to rot here.' The movie changed me in a way — because even though I felt like 'These are the guys who blow up buildings, who blow up schools, who are responsible for 9/11,' it got me thinking: What if there is that guy who accidentally got picked up on the wrong street without the right I.D., or story? It made me think no matter what, you deserved your day in a court of law. I think now there are still 143 detainees down at Guantanamo Bay, in limbo and no country will take them."

Making the film and pondering the fate of those detainees — has it colored his view of current events as the U.S. engages in military action against ISIS?

"No," he says. And then, "Well, look, I'm still one of those guys — I still am definitely a believer that there are forces of evil out there that have to be stopped. Luckily, we have some of the best troops, the best troops in the world. [The film] hasn't changed my feelings on any of that." The film, he stresses, is "an intimate character study even though it takes place within this huge facility."

As for the timing of its release amid so much dire terrorism news from Iraq and Syria — will it hurt the movie's chances?

"I always grew up with the thing that controversy sells." He shrugs. "There's so much pain going on, people need to see this film now, because people need to see the humanity in each other. ... This is not about politics, this is about human beings — humanity."

According to Garrison, because of the intensity of the scenes and surroundings, the actors, let off steam between takes. "Kristen's a great athlete, I'm a big athlete, so we built a driving range on the set of the prison. We hit like 250 golf balls a day between takes. We played basketball together with a group. We tried to laugh and have some levity just because of this dark environment and dealing with heavy stuff. It really helped to balance it. Otherwise it probably would have been a miserable shoot. But everything about it was beautiful. You know, we did the film in under 30 days. Everybody was on their A game and put 110 percent into it.

"Kristen is so good," he goes on. "I've told her, hands down, this is her best performance that she's ever given and this is going to change the game for her. I'm so proud of the work she put in on this film. I just clicked with her from day one, we just had that kind of chemistry."

"Camp X-Ray" is already proving beneficial for Garrison as well. The actor has his first major break when he played David 'Tweener' Apolskis on "Prison Break" in 2005. Then came the tragedy, the jail time, the starting over. Now he is clearly riding a burst of momentum again.

"This ride kind of started with 'Bonnie & Clyde,' last year, that really started it for me — working with Bruce Beresford and Emile Hirsch," says Garrison, who played Buck Barrow in the 2013 miniseries. Then came "Camp X-Ray," then a trip down to Austin, Texas, for a role in the TV series pilot of Robert Rodriguez' "From Dusk Till Dawn."

"I'm from Texas and he's from Texas and he's such a legend there, so that was another item off the bucket list — he's such a gifted and heartfelt man," Garrison enthuses.

Then he went on to a guest spot in the forthcoming "Breaking Bad" prequel series, "Better Call Saul," then on to the CW's "The Messengers" series.

"I went from Buck Barrow to playing a cop doing a deal with the devil," Garrison notes brightly. "It's the best year ever for me as an actor. I feel like I've gotten a second chance. I show up on set and I feel like the luckiest guy in the world."