John Wayne played Duke, a cowboy who came to San Francisco, visited the Barbary Coast, and fell in love with Flaxen, played by Ann Dvorak and got fleeced by gambler Tito Morelli, played by Joseph Schildkraut. Seeking revenge, Duke went home and learned how to gamble and how to spot cheaters from his friend Wolf, played by William Frawley. Duke returned to the Barbary Coast and won a pile of money, which he used to open a new joint on the Coast. Duke tried to get Flaxen and Tito fought him until the earthquake and fire destroyed both of their gambling houses. The special effects were not very impressive, which is unusual for a Republic movie.