Sally Warren (Susanna Foster) comes from Cambridge, Massachusetts to the Barbary Coast to find John Warren, her long-lost brother. The Barbary Coast is in turmoil, with saloon owner Dude Forante (Turhan Bey), and Rio Jordan (Alan Curtis), who runs a mission as a front for illegal activities, vying for the top spot. Forante wants the two to work together, but Jordan refuses. Sally gets a job singing at Forante's saloon and quickly becomes the star attraction. Sally receives a ring that belonged to her brother and takes it to police headquarters and convinces Police Captain Dan Martin (Thomas Gomez) to investigate. She and Martin go to Jordan for help. He claims that Fontaine, who Sally has fallen in love with, murdered Sally's brother and fabricates some incriminating evidence. Broken-hearted Sally plans to return to Cambridge, but showgirl Mickey (Collette Lyons) persuades her to stay. Sally confronts Forante, but he refuses to comment. At the mission, Sally finds evidence that Jordan may actually be her brother. Learning that Sally has returned to Forante, Jordan arms himself and goes to the saloon to confront Forante.