Meanwhile, Mary discovers that a car has been retrieved from the swamp, with Toomey's body in the trunk. Realizing the police will shortly arrive to arrest Norman, Mary returns to warn him. The phone rings in the house, Norman answers, and starts speaking to his "mother". Mary listens in and discovers that nobody is on the line with Norman. Terrified, Mary runs downstairs into the cellar, and quickly dresses up as Mother to confront Norman. Someone grabs her from behind, and she plunges the butcher knife into ... Dr. Raymond, who has sneaked back into the house. A stunned Mary runs downstairs and is confronted by a deranged Norman, who promises to cover up for "Mother". Mary tries to keep him away, repeatedly stabbing him in the hands and chest. He backs Mary into the fruit cellar to hide and slips on a pile of coal, which avalanches away from the wall, revealing Lila's body hidden behind it. Mary is now convinced that Norman had been committing the murders. She raises her knife to stab him and is shot to death by the incoming police. The sheriff inaccurately believes Lila and Mary committed all the murders.