After mugging a helpless old man, Artie Connors (Martin Sheen) and Tony Musante (Joe Ferrone) take over a subway car, terrorizing its occupants. In Stagecoach fashion, all the best and worst qualities of the passengers are brought to the surface by the presence of danger. Among the passengers are angry black man Arnold Robinson (Brock Peters) and his supplicative wife Joan Robinson (Ruby Dee), ex-alcoholic Douglas McCann (Gary Merrill), timorous Jewish couple Sam Beckerman (Jack Gilford) and Bertha Beckerman (Thelma Ritter), blowhard Bill Wilks (Ed McMahon), and homosexual Kenneth Otis (Robert Fields). It is furloughed army private Pfc. Felix Teflinger (Beau Bridges) who puts an end to the reign of terror.

otsoNY Comments: The New York City Transit Authority denied permission to film on its property, including background shots, but the filmmakers shot them anyway. Cinematographer Gerald Hirschfeld and an assistant rode the subway with a hidden camera, and when its sound was noticed, they stopped and came back later to finish the job. Hirschfeld said in an interview that he filmed in black and white in order to get "the most realistic style of photography possible"; test shots were taken in muted color but they were deemed a distraction from the desired "somber" effect. All scenes in the subway car were filmed in a studio mockup of IRT World's Fair Lo-V #5674. The producers contacted St. Louis Car Co. for original blueprints of the car and reproduced it. Lights were mounted along the car exterior and illuminated sequentially to simulate a speed of 30 mph. Subway footage was filmed by concealing the cameras inside bags. Police became suspicious when they heard whirring sounds inside the bags. The outdoor scenes of the train were filmed on and around the Bronx section of the IRT Third Avenue Line, which was demolished in 1973. The actual train trip takes longer in the film than in real life.