First-time British writer-director Tom Petch makes a powerful impression with this tough, smart war movie on a shrewdly managed small scale, about a British army patrol in Afghanistan. A small unit is deployed for what everyone hopes will be just three days in dangerous country, but a surprise night-time attack from the Allies – perhaps the Americans or even the British SAS – provokes new activity from the Taliban. Simply by virtue of its position, the unit finds itself open-endedly committed as part of a horribly dangerous and exposed frontline mission unfortunately named Operation Icarus. The men become increasingly demoralised and insubordinate. Owain Arthur is lippy Welshman Taff, Nicholas Beveney is the brooding Sol, Nav Sidhu is grumpy Smudge and Ben Righton is their well-spoken Captain Richardson, who makes a crucially misjudged decision to go easy on a scared young recruit, triggering resentment among the other ranks. Petch cleverly shows that imposing order is becoming less and less possible: the men's fear of appearing cowardly is balanced by their officers' fear of the loss of face involved in needing to invoke a higher disciplinary authority. Petch's dialogue and the resulting psychological picture are tense and plausible, and the modest digital effects needed for distant explosions actually enforce a disturbing, dreamlike atmosphere. This is an impressive debut from Petch.