After witnessing a mafia murder, slick saxophone player Joe (Tony Curtis) and his long-suffering buddy, Jerry (Jack Lemmon), hastily devise a plan to escape from Chicago. Disguising themselves as women, they join an all-female jazz band and hop a train bound for Florida. While Joe pretends to be a millionaire to win the band's sexy singer, Sugar (Marilyn Monroe), Jerry finds himself pursued by a real millionaire (Joe E. Brown) as things heat up and the mobsters close in.