Schrank breaks up the council and runs the Sharks off. He tries to get the Jets to reveal the location of the rumble and becomes increasingly frustrated when they refuse.

As the fight between Bernardo and Diesel begins, Tony arrives and tries to stop it. Bernardo taunts Tony, ridiculing his attempt to make peace, and pushing him. Riff comes to Tony's defense, punching Bernardo. When the two leaders draw their switchblades, Tony tries to intervene, but he inadvertently allows Riff to be fatally stabbed by Bernardo. Tony then kills Bernardo in a fit of rage.

Blissfully unaware of the tragedy, Maria gushes to her friends about her wedding night ("I Feel Pretty") until Chino arrives with news of Bernardo's death. She refuses to believe it, but Tony arrives and confesses, offering to turn himself in. She begs him to stay, and they make plans to run away together.

Seeing that Tony has been with Maria, Anita launches into an angry tirade against him ("A Boy Like That"). Maria counters by telling Anita how powerful love is ("I Have a Love"), and Anita realizes that Maria loves Tony as much as she had loved Bernardo.

The Jets, who have congregated at Doc's, taunt Anita with racist slurs and try to rape her. Doc arrives just in time to stop them, but Anita is furious and spitefully delivers the wrong message, telling the Jets that Chino has shot Maria dead.

Feeling there is no longer anything to live for, Tony wanders the streets, begging for Chino to shoot him too. Just as Tony sees Maria alive, Chino arrives and shoots Tony dead.

Baby John comes forward, picks up Maria's shawl, and puts it over her head. She sits quietly like a woman in mourning as the Jets and Sharks carry Tony's body away.

The production was nominated for six Tony Awards including Best Musical in 1957.

West Side Story marked Sondheim's Broadway debut.

The film was nominated for eleven Academy Awards and won ten, including George Chakiris (Bernardo) for Supporting Actor, Rita Moreno (Anita) for Supporting Actress, and Best Picture.