Steve McQueen and Richard Crenna star in this classic war drama. In China, 1926, the US gunboat San Pablo cruises the Yangtze river on a peacekeeping mission. New crew member Jake Holman (McQueen) causes friction when he insists upon looking after the San Pablo's engines himself, rather than leaving the hard labour to the Chinese helpers. Holman ruffles more feathers when he falls in love with an American missionary (Candice Bergen), and as the political climate becomes more and more volatile, he begins to question the validity of the American presence on the river.