Wild thoughts : what do wilderness films tell us about our sheltered lifestyles ?

When I see a movie about people trying to live alternative lifestyles , I think of the travel agency Jim Carrey visits in The Truman Show , with its alarming poster of an airliner getting struck by lightning ,accompanied by the slogan : ''IT COULD HAPPEN TO YOU ! '' A similar deterrent seems to be in operation whenever people reject conventional ways of living in the movies .More often than not , the parents go crazy , the kids are screws up and you come out of the cinema thinking.

For all its merits , Debra Granik's latest film Leave No Trace can't help but agree . It's the story of a father and teenage daughter who live off-grid in the middle of a national park . Despite their minimal carbon footprint , it is not exactly a sustainable lifestyle : they are evicted by the authorities ; dad (Ben Foster) is a traumatised war veteran who can't cope with civilisation ''; daughter (Thomasin Mckenzie)discovers what she's been missing-like friend.

There is often a fanatical dad at the root of these misadventures , such as Viggo Mortensen's Captain Fantastic , who also assiduously forest-schools his six children on why capitalism is wrong . Of course ,the whhels come off when they reconnect with the real world .Een worse is the Glass Castle's Woody Harrelson, who sees the ''free-spirited lifestyle lose its lustre for daughter Brie Larson when she flees to the embrace of education , gainful employment and running water . Harrison Ford goes one step further in The Mosquito coast , dragging his famil into the Central American jungle , telling the the US has been nuked .Again , he is obsessively against American consumerism , and his family have to go along with it .  

The thing with most of this films is that their basis diagnosis is correct .Our conventional lifestyle models are flawed and we all know it .But every time a movie tries out an alternative , it gets shot down like the airliner in The Truman Show . These stories flirt with radicalism but the moral is usually conservative .Leave No Trace takes a ore nuanced approach , and gets reasons people ight want to turn their backs on society.

But if you want to see a family who really make the alternative lifestyle work , you could go back to 1960 and Disney's Swiss Family Robinson .Shipwrecked on a desert island , this wholesome tribe turn it into a tropical utopia , commplete with traditional European family values .Thhere might be pirates and wild animals but it;s clearly better than Switzerlan , and when rescue arrives , most of them choose to stay put.See ? Sometimes it does work out .It could happen to .

Leave No Trace will be out on 26 June