Mia, 14, wakes up in a hospital with no memory of who she is, only knowing her name. A woman claiming to be her mother, Laura, arrives and takes her home, despite the nurse’s advice to stay longer. Mia feels something is off but goes along with it.
At Laura’s house, Mia notices odd details, like the baby photos in her room. When she sees her own photo on a milk carton labeled “MISSING” at the supermarket, she becomes even more suspicious. She memorizes the number on the carton and secretly calls it, learning from a frantic woman that she was kidnapped and her real parents have been searching for her.
Laura catches Mia making the call and locks her in the basement. Mia discovers medical notes revealing Laura’s delusional belief that Mia is her deceased daughter. She manipulates Laura into letting her out by pretending to accept her as her mother.
Once free, Mia escapes but is pursued by Laura. A police officer arrives just in time to subdue Laura and reunite Mia with her real parents. Mia finally feels safe, knowing she is back with her true family.