At the Edinburgh Filmhouse  from Fri 13 Jul 2018

Leave No Trace opens amongst lush green ferns and sparkling spider webs. 13-year-old Tom and her father Will (played assuredly by Thomasin McKenzie and Ben Foster respectively) hum contentedly while foraging and collecting firewood. Their life outdoors and outside society is gently established, as is their peaceful co-operation and mutually respectful relationship. One night Will wakes in a state – we are unsure if there is a real helicopter or if it is in his nightmares – and she soothes him with a charming conversation about her long-absent mother’s favourite colour. In this easy introduction we learn all we need to about their situation, so that the ensuing development makes complete sense.

The film is based on the novel My Abandonment (by Peter Rock, 2009), and is not about the system letting people down; indeed, the supporting characters are full of kindness and understanding, albeit within limits which are as equally extreme as living the forest life. Leave No Trace clearly establishes our collective standards – group living, state scrutiny, lack of independent decision-making and measurement of sanity through online questionnaires. In reality there is a double desertion: our impotent battle hero forsakes a normal life, and the so-called civilised world cannot embrace him on his required terms.

Throughout, the contrasts are vivid: machinery tears down trees for a flora and fauna information board to be erected; the shopping journey across the Portland bridge is noisy with grinding metal; the organised rows of Xmas trees are a stark pretence for a wilderness; and the quiet of their one-time living room and sofa as they lock the door behind them for the first time is a deadened sort of silence compared to the vibrant tranquility of the woods.

Without having to spell out the issues at play, Granik and her fellow screenwriter Anne Rosellini (with whom she collaborated on Winter’s Bone, which won the Grand Jury Prize for a dramatic film in 2010) allow us to comprehend the subtleties of this insurmountable situation. We fully empathise with Tom, a most mature teen, as she struggles with Will’s needs, and the skilfully-crafted conclusion (poignant eye contact, absence of words and a single elegiac violin) allows us to open our hearts to him as well.

Neither patronising nor sentimental despite many tender moments, the essence of the story is encapsulated in the differentiation between the communal beehive (“They can kill you if they want to, so it means a lot to have their trust”), and the isolation of the spider in its web. As the requirements of father and daughter diverge despite their love, we leave the cinema better informed about the results of war on families and the reality of the “damaged” veteran. More, we know that its impossible to hide for long.