Is it alma mater or hell? Enxi (played by Jin Ruiheng), who has lost his memories of high school, has been tormented by inexplicable illusions and auditory hallucinations since returning to his alma mater as a school supervisor. On the other side, Heying（Kim Hyun soo (played by Kim Hyun soo) also felt like he was being bewitched, and heard the eerie ghost cry in the abandoned bathroom of the school. After discovering that the supernatural event that occurred at school was related to a terrifying presence in the bathroom, the two of them diedThreats are also coming to our door. The terrifying past and secret truth hidden in memory are about to be revealed!