Captain Fantastic has brought Viggo Mortensen another round of rave reviews for his work as a widower raising his brood of six off the grid. It's practically a contemporary version of a self-sustaining hippie lifestyle. But as the Lord of the Rings veteran pointed out during a recent Herald interview, the film may initially seem as some leftish liberal fantasy but quickly morphs into something more complex. "I think it touches - without being in any way an ideological or politically motivated movie in the end – something that's very real right now," Mortensen said, "which is the negative consequences of isolation or of polarization. It's not just the Presidential campaign to have these outrageous statements being made and reactions.

"I think it actually echoes a very real problem we have as citizens right now which is a lack of communication. Sometimes a lack of any communication at all. Different camps based on race, religion, region, socio-economic class and people are not speaking to each other. Personally as a U.S. citizen I haven't remembered witnessing this degree of polarization and social tension since the '70s."

For the actor Captain Fantastic is "layered" as it shows how important it is for people on opposite sides – as his Ben Cash is pitted against his wealthy conservative father in law, deliciously played by Frank Langella - to just talk. "Not everything Ben does is condoned. The father I play of these six kids and the conservative wealthy grandfather we see making adjustments. That's what I mean when I say it speaks to the idea of being open, of changing, of being flexible. Whether it's a democracy or family unit, there's no such thing as 'perfect.' And nothing is static – it keeps changing. Every time you wake up you have to work on it.

"In the end this movie speaks to the benefits of communicating. The problems come when you isolate, when you don't speak to others, when you're not flexible or open to at least having a discourse with others who think differently than you do." Ben, he added, clearly has "made a total self sacrifice and is 100 percent committed to raising his children. That's why he's taken by surprise that his father in law has a point: He may be putting his children at risk, physically, mentally, psychologically – without intending to do that of course. When he realizes he's done it wrong it's crushing to him. And his reaction is, Everything I've done is wrong. I've got to throw it all out. But eventually with the encouragement of his kids he comes around to think that, well, the foundation of what we're doing, the concept of curiosity and total honesty and open discourse, those are not bad foundations. Maybe I can make some changes - and that's the sensible approach. Stories that make you doubt some things for a moment in your life are valuable stories."