 Agents Mickey Waters and John Flannery re-team to investigate the theft of medicinal narcotics from the S.S. Florentine. The vicious gang responsible is headed by the ruthless, but debonair Paul Vicola, who doesn t hesitate to murder anyone who stands in his way. Vicola s girlfriend is garroted when she becomes unreliable, and when go-between nightclub comic Dolly Carney poses a risk, he is thrown from his apartment window. After Waters is shot and killed trying to break into the gang s Brooklyn-based yacht club front, Flannery decides to go undercover and pose as a San Francicco drug dealer. The gang is smoked out and after a furious gun battle, Vicola is apprehended and his gang broken.