"Based on Graham Greene's gripping novel, and set during the German bombing of London, this chilling film noir espionage thriller centers on mentally unstable Stephen Neale, a man who is thrust into a world madder than the one he experienced in the asylum where he spent two years for euthanizing his terminally ill wife, an act he did not perform. The story begins after his release from the asylum. He heads for London and ends up at a carnival, not realizing that it is a Nazi sponsored organization. Those hosting the carnival see Neale and mistake him for one of their spies. He participates in a small contest and wins a nice cake. But there is more than flour and frosting in this pastry as Neale soon finds out. He hires a strange little detective to help him solve the mystery of the microfilm he found in the cake, and soon they realize that Nazi spies are afoot. Their investigations cause the demise of the detective, a crime that is neatly pinned to Neale, who goes to his girl friend for help because he knows the police will not believe him. Things get even worse when his girl, Carla, discovers that her own brother is a part of the sinister Nazi conspiracy. Both Neale and Carla find themselves trapped in a grim shadowy world where everyone they meet seems sinister and untrustworthy. For Neale, having just emerged from the madhouse, he is never quite sure his situation is real or whether he has become truly insane with paranoia. He cannot help but wonder if he is doomed to a life of trouble and ill luck."