A much performed American musical by Leonard Bernstein (1918-90), with lyrics by Stephen Sondheim (b.1930). It was first staged in 1957. The story is an updated version of Romeo and Juliet set in New York's West Side dockland area, with the Montagues and Capulets being replaced by rival teenage gangs, the Sharks and the Jets. The rivalry erupts into violence as a result of the love between Tony, one of the Jets, and Maria, the sister of the leader of the Sharks. The 1961 film version won an Oscar for best picture (Laurents, 2009).