the details of the 1927 Ruth Snyder-Judd Gray case, in which a wife murdered her husband in collusion with her lover, the prototypes for his characters Cora Papadakis and Frank Chambers in Postman. Biographer Paul Skenazy suggests that Cain was intrigued not only by their adultery and murder, but the subsequent betrayals that sent Snyder and Gray into "a self-destructive spiral." Origins of title The meaning of the title has been the subject of much speculation. William Marling, for instance, suggested that Cain may have taken the title from the sensational 1927 case of Ruth Snyder, who, like Cora in Postman, had conspired with her lover to murder her husband. Cain used the Snyder case as an inspiration for his 1943 novel Double Indemnity; Marling believed it was also a model for the plot and the title of Postman. In the real-life case, Snyder said she had prevented her husband from discovering the changes she had made to his life insurance policy by telling the postman to deliver the policy's payment notices only to her and instructing him to ring the doorbell twice as a signal indicating he had such a delivery for her. The historian Judith Flanders, however, has interpreted the title as a reference to postal customs in the Victorian era. When mail (post) was delivered, the postman knocked once to let the household know it was there: no reply was needed. When there was a telegram, however, which had to be handed over personally, he knocked twice so that the household would know to answer the door. Telegrams were expensive and usually the bringers of bad news: so a postman knocking (later, ringing) twice signaled trouble was on the way. In the preface to Double Indemnity, Cain wrote that the title of The Postman Always Rings Twice came from a discussion he had with the screenwriter Vincent Lawrence. According to Cain, Lawrence spoke of the anxiety he felt when waiting for the postman to bring him news on a submitted manuscript, noting that he would know when the postman had finally arrived because he always rang twice. In his biography of Cain, Roy Hoopes recounted the conversation between Cain and Lawrence, noting that Lawrence did not say merely that the postman always rang twice but also that he was sometimes so anxious waiting for the postman that he would go into his backyard to avoid hearing his