A mother returns home after cosmetic surgery with her head heavily bandaged. She imposes strict household rules, ignores one of her twin sons, and exhibits cruel behavior, triggering suspicions that she is an impostor. After enduring torture and restraint by the boys, she reveals that one twin is actually a hallucination born from grief over a fatal accident. The psychological tension culminates in a house fire set by the hallucinating boy, leading to her death and a spectral reunion with her children.