On a torrential rainy night, college sophomore Wu Jia accidentally runs into her secret crush, senior student Lu Zhou, at a bus stop. Amidst her joy and excitement, Li Yong, the driver of the last bus on route 22, warns her that Lu Zhou has long been dead and is not a living person. Wu Jia brushes it off, only to experience a series of bizarre events after returning home—charm papers turning black, chopsticks standing upright on their own, and non-stop midnight knocking, as if she is truly haunted by an "evil entity." Accompanied by her best friend Zhu Ya and with the "help" of senior student Lu Zhou, Wu Jia gradually comes to believe she is being harmed by the deceased Zhu Ya's "substitute curse," putting her life in grave danger. Seeking release, Wu Jia successively turns to Taoist priest Li Yong and a temple abbot for help, only to find herself trapped in an even deeper maze.