After mugging a helpless old man, two young thugs take over a Manhattan-bound subway car, trapping the 15 occupants, and one by one, proceed to bait, taunt and terrorize them. Martin Sheen, one of Hollywood's screen icons, plays one of the knife-wielding hoodlums, alongside Tony Musante. Among the melting pot of passengers are a bitterly anti-white black man and his peace-loving wife, a quarrelsome middle-aged Jewish couple, a young family with a sleeping child, two soldiers, an introverted homosexual and many more across the social and ethnic spectrum. Throughout the tense ride, not one of the passengers rises to help his beleaguered fellow riders, each individual wants only to be left alone. As the hooligans turn their menace towards the child, will the passengers finally stand up to the thugs?