Mac sees a chance to clear his name when the daughter of Harry Thyssen, the man who ordered him to let LeFabre defect, reports that her father is back from the dead. She soon drops the claim but Mac figures that he's onto something, even though his former superiors warn him off the case.

Three men join forces to murder the man who is blackmailing all of them. Meanwhile, the blackmailer hires McGill under false pretenses to find out what they're up to.