The quiet stillness of night fills the hospital. 30-year-old nurse Junko is making her usual rounds after lights out. A married woman living with her older husband, she's a responsible person who handles both her job and family duties with care. During her patrol, she discovers a room with the lights still on. Inside is patient Tsukada, absorbed in reading a book. He explains that he's reading about hypnosis because hospital life is boring, and asks Junko to let him practice hypnotism on her. Sympathizing with his loneliness—having no friends or anyone else to turn to—Junko agrees to become his test subject... Strange events unfold in the hospital at night.