German-AmericanLos Angeles-based detective Fritz Brown is hired by the mysterious caddie Fat Dog Baker, who wants him to spy on his sister Jane and her benefactor, the much older businessman Sol Kupferman. Brown recognizes Kupferman as a man he had seen at the Club Utopia before it was burned down some years before. Brown suspects Fat Dog of being an arsonist, and also discovers that Kupferman owned Club Utopia through a figurehead. Brown, thinking there might be some connection between the two men, decides to look for Fat Dog, who had mysteriously disappeared, and force him to confess, but finds him dead in Mexico instead. He has been killed by Richard Ralston, with whom Fat Dog had started an illegal trade in social welfare benefits. However, Ralston didn’t manage to find a precious notebook where Fat Dog had meticulously noted down all their illegal transactions. It’s Brown who finds it, and thus learns how Fat Dog, apart from the Utopia arson, had previously burned the houses where he had lived as foster child with his sister. Kupferman is their father, while their mother was a woman of the upper class who was forbidden from having anything to do with him because he was Jewish. To avoid scandal, Kupferman gave the children to foster parents, and he also had to bribe a corrupt officer, Haywood Cathcart, for buying his silence about the matter. Brown, who in the meantime has developed a crush on Jane, finds Cathcart out and kills him after having made him confess his criminal activities.