Viggo Mortensen, 'Captain Fantastic's' radical dad

Boot camp? Really? Just to play dad to a bunch of kids?

Viggo Mortensen has raised a son, he knew what to do - he didn't need to immerse himself in any kind of rigorous training program, did he?

Well, yes, he did.

Because Ben Cash, the character the actor plays in Captain Fantastic, is not your typical father. He's a "stick it to The Man" radical who has taken his six children deep off the grid into the forests of the Pacific Northwest, teaching them hunting and survivalist skills.

The movie, now at the Ritz East and the Carmike Ritz Center/NJ, opens with a rite of passage ceremony: the eldest son stalking a deer, capturing it, cutting its throat. Mortensen's Ben - head to toe in aboriginal war paint, like his kids - presides.

"I had to learn all kinds of unusual things that you aren't normally expected to learn for a movie," says Mortensen. "We all did."

Written and directed by Matt Ross, Captain Fantastic - a hit at Sundance, winner of a directing prize at Cannes and a top award at the Seattle International Film Festival - follows Ben and his brood as events force them to quit their compound and venture out into the world. "Everyone's so fat!" one of the kids - lean and Olympian - observes in horror.

"We were able to meet in Washington state a couple of weeks before shooting started," Mortensen, on the phone recently, reports. Ross brought Mortensen together with the young actors cast as Ben's children - George MacKay, who plays the eldest, the teens Samantha Isler, Annalise Basso and Nicholas Hamilton, and the talented pip-squeaks Shree Crooks and Charlie Shotwell. "We had a couple of weeks to hone the skills that we had to have to show on screen. Every day we did rock climbing, martial arts, physical exercise, played a lot of music, jammed together."

Mortensen had to learn, "more or less credibly," the bagpipes. He worked on his guitar chops.

"Some of the girls had to learn animal slaughter and skinning," he says. "But it all helped, because not only did everybody look like they could do the things they were meant to do, but there was also a bond that was created between us in a very organic way. . ..

"By the first day of shooting we knew what was expected, we enjoyed each other's company, and I think that's a big part of the reason why what you see on screen and what you feel watching this family - that they really are a family and that they do know each other and have known each other for years.

"Everything we went through helped us create that illusion."

It also helped that Mortensen, 57, famous as Aragorn the heroic stranger of The Lord of the Rings, was already familiar with much of the reading material that Ross had recommended by way of preparation, research. Noam Chomsky, Karl Marx, The Brothers Karamazov, you name it, Mortensen had read it.

The actor has also long owned land in the northwestern corner of Idaho, just a day's drive east from where the Captain Fantastic encampment was established.

"It's in the middle of a forest," he says of his Idaho property. "And I have a tepee and a house . . .. I go there as often as I can, and I went there before the movie, before we even did that boot camp. I filled up a pickup with a bunch of things that we ended up using, including plants for the garden that you see in the movie, and boxes of books."

Speaking of which, Mortensen owns his own imprint, Perceval Press, publishing books on Cuban art, Russian criminal tattoos, poetry, music. Authors include Exene Cervenka, the co-founder of the pivotal L.A. punk band X (and Mortensen's ex-wife), the late poet Scott Weinberg, documentarian Alix Lambert and Mortensen himself, who has long pursued photography:

"I'm preparing a new book of photographs," he says. "I've repaired a couple of my analog cameras, my film cameras . . . I have been shooting digital, which is great, this past decade. But there's something about loading film, and shooting it, your exposure and your framing and then that surprise when you go to develop it. Oh, I didn't expect that!"

Of course, there has been something of the real Mortensen in all of the characters he's portrayed down through the years - from the Navy SEAL master chief in 1997's G.I. Jane ...

... to the itinerant clothing merchant who seduces a repressed wife in the 1999 romance A Walk on the Moon ...

... to the Russian mob "cleaner" in 2007's Eastern Promises.

"You bring your voice and your body to the role - any role - and then you bring your skill set or your life experience," he explains.

But while the actor concedes that Captain Fantastic's Ben hewed closer to his own persona than a lot of his previous work, it's not as close as people might think.

"There are certain aspects of Ben that certainly I related to, responded to," he says. "But there were a lot of things that were new. His emotional journey and his energy as a father, his body language. . . . On an intellectual level, emotional level, I'd never played a character quite like that. . . . As a whole, it was probably one of the most - if not the most - complex and challenging journies I've had as an actor. "

Mortensen says that one of the reasons audiences are responding to the offbeat, sometimes funny, sometimes tough Captain Fantastic story line, is that beneath all the revolutionary rhetoric, the antiestablishment ethos, its themes are universal.

"You start watching the movie and you think it's going to be some liberal utopian fantasy and the family is going to come up against all these conservative people and obstacles, but that would have been a much more limited type of story," he says. "It's not just a movie that liberals can respond to, or conservatives. Everybody is somebody's son or daughter. You don't need to be a parent to appreciate this, to get something from it."

And Ross' screenplay is nuanced, smart. Mortensen's Ben can be a warm, loving dad, but he's also a tyrant, a zealot. Arrogant. Flawed.

"The movie addresses the consequences of not communicating, not being open to opinions other than your own, not being able to come to grips with the fact that you're on the wrong track at times," the actor says.

"Which is inevitable, because there's no such thing as a perfect father, a perfect person. A perfect relationship is something that requires daily effort, and attention must be paid. And if attention isn't paid, then you're going to have trouble.

"Life is a game that moves as you play, and if you don't move, you don't play very well."

srea@phillynews.com

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