Magnus (Keir Dullea) and Julia Lofting (Mia Farrow) have a happy marriage until one morning when their daughter Kate (Sophie Ward) begins choking. Unsure what to do, Julia attempts a tracheotomy, inadvertently causing Kate's death. Julia heads to a sanitarium to recover, and when Magnus asks that she come home, she prefers to buy a new house in London and live alone there. Magnus frets over Julia's sanity, while Julia becomes convinced that her house is haunted by the spirit of a little girl.