In Prohibition-era Chicago, musicians Joe (Tony Curtis) and Jerry (Jack Lemmon) disguise themselves as women to escape mobsters they witnessed committing a murder. Broke, terrified, and desperate, they join an all-female band headed to Miami by train, befriending vocalist Sugar Kane along the way. On their journey, Joe woos Sugar while pretending to be a millionaire named Junior, but Jerry's rival suitor Osgood Fielding III complicates matters. As Spats Colombo and his gang close in on them, the two musicians must navigate deception, cross-dressing, and romance to escape with their lives.