Do-yeon, a typical female college student in her 20s, has been recently tormented by a severe stalker. Despite reporting it to the police, they only provide superficial responses. One day, the stalker manages to break into Do-yeon's house, and after a physical struggle, she ends up killing the stalker by striking his head with a snow globe that was on a shelf.

When the app is launched, a ghost appears. Developed by four young adults, the app becomes the centerpiece of a livestream where they venture into a supposedly haunted mountain to prove its authenticity—only to meet a grim fate.