Shortly before millionaire John Willis was about to get married, psychiatrist Harry S. Blair visited him and told him that a few years before his marriage to John's wife to be, Nancy, he had warned him that Nancy was mentally unbalanced. Blair tells the following story: after a whirlwind romance in Florida, Blair married Nancy and began psychiatric treatment in New York. One day, artist Norman Clyde came to his office and told an innocent person that he was about to be executed in a Singapore prison, and that Nancy was the reason for his unjust imprisonment. Grief stricken Clyde then explained to curious Blair that three years ago, Clyde met Nancy while she was registering for his art class. Nancy's maiden name was Monks. Clyde, who was moody, quickly fell in love with Nancy's honest charm and beauty. Nancy is a secretary who introduced Clyde to her boss, millionaire Andrew Bonner, and convinced Bonner to display his paintings at a private exhibition of Clyde. To Nancy's delight, Clyde's painting won first prize in the exhibition, depicting the tragic character Cassandra she modeled. This night was perfect until a guest's expensive bracelet was stolen, and Clyde later found it in Nancy's wallet. After Clyde confronted confused Nancy about the theft case, she told the following story to explain her behavior: when she was a child, Nancy lived with her butler mother in Willis' luxurious home and played with Willis' little daughter Karen. Although Karen wanted to invite Nancy to her upcoming birthday party, Mrs. Willis refused to allow lower class Nancy to attend. As a true friend, Karen promised Nancy a pin that the customer was receiving. However, when Karen realized she didn't have any extra pins, she gave Nancy the beautiful little necklace she had just received from her mother. Nancy's subsequent joy was soon shattered, as Mrs. Willis demanded that she return the small lock. Later, the lock was found missing and Nancy was accused of theft. Although Nancy's mother soon discovered the small necklace in Karen's dress, Mrs. Willis refused to believe Nancy, And force her Frankly, as an adult, Nancy later admitted to Clyde that this childhood humiliation had led her to unconsciously want to steal bracelets at the party. After a tolerant Clyde anonymously returned the bracelet, he and Nancy continued their relationship until the Bonner couple's next gathering. Clyde suspected that absent Nancy had spent the night in Bonner's arms, so he left the party to search for her and saw her leave after two gunshots Mrs. Bonner's bedroom. Bonner was found murdered and Mrs. Bonner's diamond necklace was stolen. Despite Nancy and Clyde being interrogated, Myron Dexter, the personal servant, was ultimately found guilty and sentenced to death. However, Clyde strongly suspected Nancy, but Nancy angrily insisted on her innocence and went to Florida. Returning to the office, Blair defended Nancy to Clyde, but invited him to stay at home that night. When facing each other, Nancy denied everything and told Clyde it was just jealousy. The next day, Dexter was executed, and Clyde, full of guilt, jumped out of the window of Blair's office and walked towards death. To avoid scandal, Blair and Nancy moved to the UK. After the outbreak of World War II, Blair voluntarily provided medical services, and Nancy became an ambulance driver. Nancy expressed concern about Blair's health and insisted that they go on vacation to Lord and Lady Windham's estate. Just as they left, Blair learned that one of Mrs. Windham's valuable jewelry had been stolen. Blair suspected Nancy, but could not prove anything until a bomb destroyed their apartment and exposed the stolen jewelry she had hidden. Despite facing it directly, Nancy still denied any wrongdoing and divorced Blair after his mental breakdown. Returning to John's study, Blair, like Clyde before him, tried to persuade John to give up Nancy, who is now using the name Barton. However, when Nancy told Blair that he was still suffering from a mental breakdown, John believed him. Just before the wedding, Nancy's future mother-in-law, the unsuspecting Mrs. Willis, gave her the same small pendant she had taken and told her it was a precious heirloom. This necklace made Nancy feel guilty and she collapsed hysterically in front of the altar. Nancy was later taken to an institution, and John sadly realized the truth of Blair's story, but was determined to help Nancy overcome the crisis.