Set in a suburban Los Angeles neighborhood, the film opens on Anne Gwynne (Foster), a 36-year-old ex-movie star turned housewife. Following a tragic pregnancy loss, Anne becomes fixated on perfecting her role as a mother to daughter Kate (Kathleen Turner in an uncredited role). After a mental breakdown, Anne begins infiltrating the lives of those around her—neighbors, friends, and even her own family—with increasingly manipulative and destructive intent. The film’s title metaphor, “the hand that rocks the cradle,” is recontextualized from its traditional pro-life connotations to a chilling symbol of psychological dominion.