In World War II Burma, prison camp commander Colonel Saito (Sessue Hayakawa) insists that his prisoners must build a bridge over the River Kwai. The Americans, lead by American Navy Commander Shears (William Holden), comply but the newly arrived British contingent refuses. Hayakawa plans to execute the British but Major Clipton (James Donald), the camp medical officer, persuades him otherwise. Instead Saito punishes the British, first by forcing them to stand in the hot sun and then sending British leader Colonel Nicholson (Alec Guinness) to solitary confinement and his officers to a punishment cage. Commander Shears manages to escape the camp and, while recovering from his wounds, is approached by Major Warden (Jack Hawkins), a member of the British Special Forces, who wants him to help his squad of commandos destroy the bridge. Knowing a secret about Shears, Warden is able to force him to lead them to the newly completed bridge, where ironically Colonel Nicholson has taken over construction to keep his men going. Shears and Lieutenant Joyce (Geoffrey Horne) set the explosives, which eventually do their work in spectacular fashion, but only after a series of surprising and tragic twists and turns.