Shopgirl Rhoda Regan is in love with the Harmony Lad, the leader of a New York street gang called the Hudson Dusters. After two gang murders are committed in the Pepper Box, a local cabaret, the Harmony Lad promises his worried sweetheart that he will abandon the gang for a singing career, and true to his word, he soon accepts a job on the Pepper Box stage. When Stumpy Darcy, the new leader of the Dusters, kills rival gang leader Wedge Barker, who had flirted with Stumpy's girlfriend, Mamie Conlon, the Harmony Lad flees to New Jersey to escape police interrogation.