Blood Brothers is a musical with book, lyrics, and music by Willy Russell and produced by Bill Kenwright. The story is a contemporary nature versus nurture plot, revolving around fraternal twins Mickey and Eddie, who were separated at birth, one subsequently being raised in a wealthy family, the other in a poor family. The different environments take the twins to opposite ends of the social spectrum, one becoming a councillor, and the other unemployed and in prison. They both fall in love with the same girl, causing a rift in their friendship and leading to the tragic death of both brothers. Russell says that his work was based on a one-act play that he read as a child "about two babies switched at birth ... it became the seed for Blood Brothers."

William Russell is an English dramatist, lyricist and composer. His best known works are Educating Rita, Shirley Valentine, Blood Brothers and Our Day Out.