En route to New York, Simon Templar, the Saint, saves Ruth Summers from being cheated during a shipboard card game. Upon docking, Ruth disappears and Simon's attentions turn toward helping his friend, Inspector Henry Fernack, who has been ousted from office after being framed for bribery by a syndicate of race track gamblers that he was about to arrest. The syndicate is headed by Ben Egan, and fellow member Rocky Weldon hires crook Pearly Gates to rob Egan's safe. Egan catches Pearly breaking into his safe, however, and after snapping his picture, sends him back to Rocky. As soon as Pearly leaves, Egan is murdered, and soon after, Fernack arrives at Egan's house, followed by Simon. Finding the incriminating photo of Pearly, Simon visits Rocky's club, where he encounters Ruth and blackmails Pearly into helping him clear Fernack. Things look bad for Fernack when Rocky is found murdered and Fernack again appears at the scene of the crime. Simon then decides to kidnap a third syndicate member, Leo Sloan, and terrify him into confessing, but Sloan is also murdered before he can talk. Of the five original members, only Sam Reese and Max Bremer remain alive, and Simon decides to break into Reese's apartment to await the killer. Much to his surprise, Ruth appears and confesses that she has killed the others in revenge for the murder of her brother Johnny, a witness in the case against the syndicate. Simon convinces Ruth to help him ring a confession from Reese, but his plan is thwarted when the police arrive to arrest Simon and Fernack. Escaping his captors, Simon plants a police radio in Bremer's office and then tricks Reese and Bremer into confessing to the murder of Summers and the frame-up of Fernack. After tracing the signal, the police come to arrest Bremer and Reese, but Bremer escapes, only to meet his death in a shootout with Ruth. The wounded Ruth then dies in Simon's arms.