The appearance of Leave No Trace reminded us what a great film-maker Debra Granik is, and what a long time it has been since her last feature, Winter’s Bone in 2010, the film which made a star of Jennifer Lawrence. Lawrence has hardly been out of the spotlight while Granik has been a little forgotten. Well, this superlative film has brought her back. Ben Foster and Thomasin McKenzie play Will and Tom, a middle-aged military veteran and his 13-year-old daughter, who are living a Thoreau-type guerrilla existence in a huge national park in Portland, Oregon. They are trained and disciplined: they have a secret camp with tarps and cooking implements and they know how to stay undercover and avoid the authorities. Periodically, Will can sneak into the city, pick up his free prescription for painkiller meds which he sells on the black market, and uses the cash to buy food and supplies which he brings back into the jungle. It seems like the ideal setup, but one day they are spotted, and things come to a crisis.

Will and Tom’s apparent belief in an eternal, Edenic present is what is so striking. There is no sense that either of them have thought about what it is going to mean when Tom gets too old to share a tent with her dad (surely that moment has already arrived?) or when she wants to meet people her own age. And that question is brought into sharp focus when they are in fact captured – there is hardly any other word for it – and subjected to psychiatric assessment. In some ways, the clinical coldness of this assessment is exactly the kind of soullessness that they were trying to get away from. And yet you can see that the assessment is asking them to think about their lives in ways they had perhaps always avoided.

In any case, being caught is evidently an occupational hazard for them: they know how to fake being complaint, going along with the idea of being rehabilitated into society, before discreetly slipping away. It’s a film with things to say about nature and our relationship to it, and how people who do not want to consume, to produce, to surf the waste-byproducts of economic growth which despoil the natural world, should not be labelled as eccentrics or dropouts or tramps. Yet neither is it sentimental about what the father is putting his daughter through. Wonderful performances here from Foster and McKenzie.