Kang Yu-jin, a wealthy biology professor doing a butterfly field study, takes in a new housemaid; the young woman, Mi-ok, is the daughter of a shaman priestess who recently died in a house fire. At first, Yu-jin and his wife, Seon-hee, welcome Mi-ok into their home, but Seon-hee begins to have misgivings when she sees a strange wooden doll that the maid has brought with her. Having suffered from nightmares about exactly the same doll, Seon-hee becomes increasingly suspicious that Mi-ok is trying to kill her and usurp her household. In a fit of madness, Seon-hee causes Mi-ok to fall to her death. From then on, Seon-hee is tormented by visions of the doll attacking her.