The bitter memory of witnessing a buddy getting shot in the face while on a tour of duty in Afghanistan make the reintroduction of Sam (James d’Arcy) into polite British society an uneasy one. Riding on his tough-guy credentials, he accepts a job as a prison warden and it’s not long before he graduates from wet-behind-the-ears rookie to drug-Hoovering, lapdance-loving hardnut. Aside from some appealing performances – Noel Clarke is surprisingly effective as the kingpin of D-block – Reg Traviss’s overlong thriller spews out clichés from the off. While hardly a genre that allows for subtlety, matters aren’t helped by awkwardly blunt dialogue, especially d’Arcy’s unintentionally amusing proclamations that he ‘doesn’t play by the rules’ and that his life is ‘totally fucked-up’. There are also far too many characters, all bundled in to try to cloud the identity of a mystery snitch who you’ll most likely have identified the moment he swaggers on to the screen.