The 1996 non-fiction bestseller Into the Wild chronicled the final two years of Christopher McCandless, an idealistic college graduate who gave his savings to charity and then set off for America’s wildest regions. His dead body was later discovered by a moose hunter in the Alaskan wilderness.

To play the part of McCandless in Sean Penn’s film version of the story, which debuts at the Osio Cinemas on Friday, 22-year-old actor Emile Hirsch had to survive a grueling eight-month shoot in a variety of far flung locales that included the region north of Alaska’s Denali, and Slab City, a squatter’s camp in the California desert.

The young actor – who starred in 2005’s Lords of Dogtown as troubled real-life skateboarder Jay Adams, and portrayed a variation on drug-dealer Jesse James’ Hollywood in 2006’s Alpha Dog – did his own stunts in the new film. These included racing through a turbulent portion of the Colorado River in a kayak, and hacking a dead moose into cuts of meat.

After an exhausting day during which Hirsch had taped an upcoming appearance on The Oprah Winfrey Show and received the Mill Valley Film Festival’s Spotlight Award for his portrayal of McCandless, the actor sits in a suite inside San Francisco’s hip and luxurious Clift Hotel for a full day of interviews with various members of the press.

Far removed from the harsh realities of the natural world depicted in Into the Wild, Hirsch sits at a table in his suite, eating cereal and sipping coffee as we talk about his experiences on the set. I ask him why Krakauer’s book appealed to him. “The wanderlust,” he says simply. “The adventure. The same thing that kind of infected people when they read On the Road… If it had been a story about flight or fleeing from a family, or if he just went a block away and worked on a train set, no one would have cared.”

The actor, who grew up in Los Angeles and Santa Fe, says that he had only a few experiences in nature before he went headlong into the natural world for the shooting of the film. He had hiked around in Topanga State Park and recently walked to the Pyramid of the Sun in Mexico when he was shooting a film called The Air I Breathe down there. As a child he spent some time outdoors in the mountains around Santa Fe. “I’d been to a lot of summer camps,” he says.

Despite such limited experience Hirsch was game to take on a lot of potentially dangerous stunts during filming, but it was the sequence in which he was supposed to kayak down a frothing Colorado River that weighed heavily on his mind before shooting. “People get weird about water,” he says. “They get panicky and fidgety, and I’m one of those people a lot of times.”

Despite his fears, Hirsch pulls off a very impressive paddle through raging whitewater in the film. The young actor admits it was because he was tricked that he didn’t have time to get worried in advance. “I was kind of blindsided by the size of the rapid,” he says. “I thought it was going to be this really small one, and then we passed it in the boat. I go to Sean: ‘Isn’t that the rapid?’ He says: ‘That’s not a rapid.’ We finally hit this other rapid – which was slammin’ big. Luckily, I didn’t have too much time to dwell on it.”

While navigating the river’s churning hydraulics in a kayak, Hirsch was aided by his own adrenaline. “It was just this terrified exhilaration,” he says of the experience.

One highlight for Hirsch was getting to work with Sean Penn. “We got along great,” Hirsch says of his relationship with the actor-director. “I think we had mutual commitment to the project and really loved the story. Because of that we had a really easy dialogue even though the stuff we were doing was really hard.”

Having experienced so much during the eight-month shoot, Hirsch is bound to have been changed by some of his experiences on the set. “It’s funny,” he says. “I feel a bit older.”

Now that Hirsch has returned to the comfortable life of a young Hollywood star, I ask if he would ever like to return to some of the wild areas he visited during the shooting of Into the Wild. “I would love to go check out Alaska again,” he says. “Get back on the Colorado River and the Grand Canyon and do that again – this time with a proper life jacket.”

Into the Wild opens Friday Oct. 5 at the Osio Cinemas, 350 Alvarado St., Monterey..