A small-town detective searching for a missing man has only one lead: a connection with a New York prostitute.

Suffering from insomnia, disturbed loner Travis Bickle (Robert De Niro) takes a job as a New York City cabbie, haunting the streets nightly, growing increasingly detached from reality as he dreams of cleaning up the filthy city. When Travis meets pretty campaign worker Betsy (Cybill Shepherd), he becomes obsessed with the idea of saving the world, first plotting to assassinate a presidential candidate, then directing his attentions toward rescuing 12-year-old prostitute Iris (Jodie Foster).

In this acclaimed Robert Altman drama, the lives of numerous people in the Tennessee capital intersect in unpredictable ways. Delbert Reese (Ned Beatty) is a lawyer and political organizer who is having difficulties in his marriage to Linnea (Lily Tomlin), a gospel vocalist. Other performers heavily featured in this renowned ensemble production include country singers Barbara Jean (Ronee Blakley) and Connie White (Karen Black), who are rivals in the city's thriving music scene.

When inexperienced criminal Sonny Wortzik (Al Pacino) leads a bank robbery in Brooklyn, things quickly go wrong, and a hostage situation develops. As Sonny and his accomplice, Sal Naturile (John Cazale), try desperately to remain in control, a media circus develops and the FBI arrives, creating even more tension. Gradually, Sonny's surprising motivations behind the robbery are revealed, and his standoff with law enforcement moves toward its inevitable end.