Newly-divorced doctor Sarah Cassidy and her 17-year-old daughter Elissa move to a small, upscale
suburb. They are disturbed to discover the house they are moving into is on the same street as the house in which a girl named Carrie-Anne Jacobson killed her parents four years prior. She fled and was never seen again, leaving her brother Ryan as the sole survivor. Ryan now lives alone in the house and is hated by his neighbors; Bill Weaver, a local police officer, is his only supporter. Elissa's relationship with her mother becomes rocky when she starts seeing Ryan against Sarah's wishes. Ryan confides in Elissa that Carrie-Anne fell from a
swing when they were little; he was supposed to be watching her while their parents were getting high on drugs. The
brain damage from the accident made her extremely aggressive, leading to their parents' murder. Ryan is revealed to be secretly taking care of a now-grown Carrie-Anne in a hidden room in the house. Carrie-Anne escapes and approaches a couple in a car while brandishing a kitchen knife. Ryan accidentally kills her while trying to hide her. Grieving, he goes to a diner, where he meets a kind waitress named Peggy Johns. One night, a group of unruly high school boys pick a fight with him; he breaks one of their legs in self-defense and flees. Elissa drives to his house, finds tampons in the garbage, and discovers the secret room. She is attacked by Carrie-Anne, revealed to be Peggy. Ryan restrains "Carrie-Anne" as Elissa finds blue contact lenses and Peggy's wallet in the kitchen. Ryan has kidnapped Peggy and attempted to make her look like his sister. He knocks Elissa unconscious. Elissa wakes tied to a chair. Ryan reveals that Carrie Anne didn't kill their parents. She had actually died during the accident on the swing set. It was Ryan who killed their parents after suffering years of abuse because they blamed him for his sister's death. The "Carrie Annes" he has been keeping in the basement were kidnapped women he made up to look just like his sister. He decides to get rid of Peggy and make Elissa his new Carrie Anne. Officer Weaver arrives but Ryan stabs him to death. Elissa tries to escape in Ryan's car, but he knocks her out with
chloroform and traps her in the car trunk with Peggy's body. Sarah arrives and is stabbed by Ryan. Elissa escapes and shoots Ryan with Weaver's gun. When he attempts to stab her, Sarah strikes him with a hammer. Elissa and Sarah move out and Ryan is placed in a
psychiatric ward. He begins to
hear the voices of his deceased parents calling him Carrie-Anne. A
flashback reveals a young Ryan about to blow out birthday candles while dressed in girl's clothing. His mother refers to him as Carrie Anne; he protests that he is Ryan. She violently slaps him across the face in response, insisting he is Carrie Anne. ==Cast==