Two powerful gangsters, Mike Palmero (played by Leo Carrillo) and Tony Ricca (played by Boris Karloff), are in a fierce competition for control of the bootlegging business. Maria (played by Constance Cummings), Palmero's daughter, is afraid of her father and disapproves of his illegal activities. Despite this, she falls in love with Marco (played by Robert Young), the son of Tony Ricca. As the gang war intensifies, there are more casualties. Fearing that her father will harm Marco, Maria keeps their relationship a secret. When Mike Palmero discovers that Marco and Maria have married, he orders for Marco's death. But Marco's mother ultimately kills Mike, putting an end to the violence.