A relentless criminal mastermind orchestrates a succession of baffling crimes and menacing blackmails, using disguises, ingenious devices, and daring escapes while various pursuers and associates attempt to stop him. The episodic narrative moves through street brawls, secret plots, whispered threats sent by wireless, and dramatic kidnappings, and includes a woman’s self-sacrifice that intensifies the stakes. Chapters alternate suspenseful set pieces and puzzling clues as repeated captures, counterplots, and narrow escapes keep resolution uncertain until the close.