20世纪五六十年代，慌乱的少女克莉丝汀（艾伯·赫德 Amber Heard 饰）奔走在旷野之上，她点燃了附近的农舍，不过最后还是被警察抓去，继而送进了北湾精神病院。由于克莉丝汀极具攻击性，因此她被安排进了特殊病房，在这里她的自由受到限制，能见到的除了冷冰冰的医生护士，便是隔壁的女孩艾米莉（玛米艾·古默 Mamie Gummer 饰）、柔伊（劳拉·雷赫 Laura-Leigh 饰）、艾瑞丝（琳德赛·方赛卡 Lyndsy Fonseca 饰）等人。 　　从女孩们的口中，克莉丝汀得知神秘的斯金格医生（杰拉德·哈瑞斯 Jared Harris 饰）似乎一直在女孩们的身上做某项实验，与此同时，仿佛有一个恐怖的恶灵逡巡在精神病院内，时刻准备夺取女孩们的性命……In 1966, in North Bend, Oregon, the runaway Kristen is captured by the police after burning down a farmhouse and is locked in the North Bend Psychiatric Hospital. Kristen is introduced to Dr. Gerald Stringer, who uses experimental therapy. Then she meets the inmates Emily, Sarah, Zoey and Iris and the tough nurse Lundt. During the night and in the shower later, Kristen sees the ghost of a woman and she learns that she is Alice Leigh Hudson, a mysterious wicked intern that has disappeared. When Iris is ready to go home, she is attacked by the ghost of Alice in the basement and murdered. She vanishes and the inmates decide to seek Iris out. Then Sarah is abducted by the Alice and also killed; the next one is Emily. Meanwhile Kristen escapes from her room and meets Zoey, expecting to protect her. However, Zoey is kidnapped by Alice and Kristen runs to Dr. Stringer's office. She snoops his desk and finds a report with the truth about Alice.