Xiaolan, an 11-year-old girl, meets up with her classmates to experience a horror-themed escape room game. The game features 21 levels in which "monsters" played by the staff are infested.
When Xiaolan passed the 20th level, she heard the sound of chainsaws and songs. She turned around to find a man wearing a terror mask and holding a blood axe chasing her. Xiaolan was so frightened that she cried and ran, and fell because she was unfamiliar with the environment.