The Silenced (2015)
A sickly girl Ju-ran transfers to a new sanitorium boarding school to regain health. But she discovers that students are disappearing and notices abnormal changes happening to her body. She suspects the school for what's happening and tries to discover what secret is hidden.
Stars
Park Bo-young, Uhm Ji-won, Park So-dam, Kong Ye-ji, Sim Hee-seop