In 2003 a woman in New York asked her husband to play a "sensory game." She blindfolded him, handcuffed him to a chair and asked him to guess what she was touching him with, and then she stabbed him in the chest. Sheila Davalloo and Paul Christos both worked in the medical field, and their marriage had gone cold. Paul agreed to the game because he thought it might bring them back together. When the knife went in, she said it was an accident and stabbed him again. He begged her to call 911, and she told him the lines were busy. When she finally drove him to the hospital, she stopped in the parking lot, opened the back door and stabbed him a third time, nicking his heart, but Paul fought her off and survived. Detectives let her believe he was dead, and she talked to them for 10 hours, sure nobody would ever hear his side. Then they checked her phone and found her last call was to a man named Nelson, the boyfriend of a young woman who had been stabbed to death in her apartment five months earlier. Sheila's blood turned up on that woman's bathroom tap. In the video below Piers Morgan asks her why she did it. She touches her chest and says Paul cut her first, that he beat her for years with his fists and she always took it, and then she corrects herself and calls it consensual, part of the game. "I couldn't take it anymore. I guess I just wanted him to see how it felt." Paul swore under oath that he never once hit her. At the murder trial Sheila chose to defend herself, so the jury listened to her voice for weeks before they heard the 911 call from the day Anna Lisa died, a woman saying a man had attacked her neighbor, and they recognized it as hers. She got 25 years for Paul and 50 for Anna Lisa, and she still says she wasn't there. Was she a battered wife who finally snapped, or a killer who invented the perfect excuse ten years too late?