 While Carrie is at the prom, Margaret snaps mentally; she is seen pacing in the kitchen, then beginning to chop a carrot with a butcher knife, and continuing to chop the cutting board even after the carrot rolls away.After Carrie returns home after unleashing her powers at the prom (killing almost everyone there), Margaret, who has lit thousands of candles all over the house, tells her about the night she was conceived by marital rape, then stabs her in the back with the butcher knife while leading her in the Lord's Prayer.As Carrie tries to crawl away, Margaret makes a cross motion with the knife and stalks her through the house with a delirious look in her eyes.