An attractive and aristocratic-looking girl of apparently quite ordinary origin has always had good reason to believe she was not the daughter of her mother's husband. Losing both her parents, she seeks her fortune in London, makes her way into the social world and marries into a titled family. Then, through no fault of her own, she becomes involved in the death of a scoundrel who was attempting to blackmail her. Thanks to the help of the one-time great detective, Gilbert Larose, she at first eludes the law, though Scotland Yard is quite certain that she is the guilty woman.