In the Haibei People's Hospital, Qinghai province, China, the present day on the night of a full moon, a patient is murdered by a syringe through her chest. This adds stress to the hospital's heart surgeon Gu Zhensheng who had recently lost his wife Xia Xue (Liu Yuxin) to an illness. Since his wife's death, Gu has been suffering from nightmares that has affected his work, and Xia Xue's younger sister, Nurse Xia Xiaoyu (Yang Yuyu) also is emotionally disturbed. The Hospital's director Wen Miao (Li Nian) is due for an operation for a weak heart. She's the fiancée of Mai Xiangyu (Francis Ng) the hospital's psychologist. Nurse Wu can't forgive Mai for breaking up with her and threatens to show his fiancée old photos of them having sex. One night, Wu is murdered in the same way as the old female patient. Gu tells hospital director Wen that Mai has been acting strangely lately, and Mai also tells him the same thing about Gu.