影片讲述了1938年一位少女在转学至疗养寄宿学校之后所经历的诡异事件。朴宝英饰演的珠兰转学到京城学校开始寄宿生活，严志媛饰演的校长把珠兰介绍给学生们并希望大家好好相处。然而在寄宿学校里却接连发生了神秘事件，少女们接连消失，珠兰也陷入了混乱。Korea in year 1938. Joo-ran is a talented girl who is transferred to the Gyeongseong Boarding School in the near of Keijyo; the later Seoul. But Gyeongseong School isn't a normal school. The location of the school is kept a secret and even its existence is not known to public, though life seems to be not different from other boarding schools. Joo-ran accidentally learns, that there is another girl who has exactly the same name. She is curious, but the girl disappears right after Joo-ran met her. Now the young girl is confident, that there is something wrong about the Gyeongseong School. Joo-ran starts a risky research to uncover the secrets surrounding the school, which puts her life in danger.