Famous for a snooker ball scene that absolutely does not involve snooker, Alan Clarke’s landmark Brit drama is brilliantly acted – not least in its central turn by a young Ray Winstone. Playing borstal inmate Carlin, he looks about 16 (though was actually 22 at the time) and exudes a reined-in ferocity as he pursues alpha status in a block run by cruel, bullying screws. Somehow the film’s anger never overwhelms its craft, with Clarke’s camera always in just the right place to capture its seething undercurrent of nastiness and hurt. Bruising but essential.