Shanghai, Valentine's Day, 14 Feb 2011. Hairdresser Guan Wenxin (Sandrine Pinna), 27, the illegitimate daughter of a French man and a Chinese woman, is kidnapped by her onetime best friend, rich girl Dai Anni (Christa Yan), immobilised with muscle relaxants, and held prisoner in a flat. Both had fallen for the same man, teacher Luo Jia (Ren Quan), while at university, and An-ni had lived with him for two years in the US; but after Luo Jia chose to propose to Wenxin, Anni has returned from the US to get her revenge. Anni tries to electrocute Wenxin in a bathtub but the latter escapes; during their subsequent fight, Wenxin is knocked unconscious. She wakes up, exactly three months later, on a road in the rain. After finding Luo Jia, she discovers the flat in which she was held prisoner - immediately opposite Luo Jia's - is now empty and Anni has disappeared. Anni's father (Cui Jie), the psychiatrist head of Puen Hospital, confirms he last got a message from his daughter on 14 Feb; after putting Wenxin through some tests, he confirms she has amnesia. Staying with Luo Jia, Wenxin keeps getting horrific visions. One day in the metro she meets Wu Guangming (Lee Wei), an artist who says he found her three months ago and let her live at his flat. Luo Jia then tells Wenxin that the body of Anni has been found in the sea near a greenhouse she owned outside the city; the body is badly decayed after being in the water for three months. The next day, at Anni's funeral, Wenxin suddenly seems to become possessed by her personality, saying she was pregnant by Luo Jia and Wenxin was responsible for the loss of her baby. Wenxin now starts to believe that Anni's ghost has taken over possession of her body.