During World War Two, a collection of hardened Allied prisoners are kept in an 'escape-proof' German camp. Led by the 'Big X' (Richard Attenborough), the men formulate a plan for a mass breakout, digging three tunnels - Tom, Dick and Harry. The team behind the escape includes a near-blind forger of passports (Donald Pleasance), a claustrophobic tunnel-digger (Charles Bronson) and the independent American 'Cooler King' (Steve McQueen). With men like that on their side, how can they fail?