The film tells the strange story of a young girl who transferred to a convalescent boarding school in 1938. Zhu Lan, played by Park Baoying, transferred to Beijing School to start boarding life, while the headmaster played by Yan Zhiyuan introduced Zhu Lan to the students and hoped that they would get along well. However, mysterious events occurred one after another in the boarding school, the girls disappeared one after another, and Zhulan fell into chaos.