At Gadang Elementary School, there is a mysterious jar buried in the schoolyard known as the "Ghost Jar." According to an old legend, the area was once a cemetery overrun by ghosts, until an exorcist captured them all and sealed them inside a stone jar. One day, Dongjae, who always carries a strange pouch on his waist, tells Darem, who has difficulty walking, that the time has come and invites him to the Ghost Jar that night. When Darem arrives at the school, the jar begins to shake and emits an eerie sound. Guided by Dongjae, Darem reluctantly opens the lid of the jar, only to find himself face-to-face with three evil spirits...