Helen Morgan (Ann Blyth) is a singer and dancer working at a carnival. Larry Maddux (Paul Newman), a bootlegger, recognizes her talent and agrees to promote her, and the two begin a tumultuous romantic relationship. Through his conniving ways, Larry propels Helen to stardom. She lands a starring role in a hit Broadway musical, "Showboat," and later maintains a residency at her own nightclub. But, when she realizes Larry is only with her for her money, Helen succumbs to alcoholism.