During an investigation into a mass murder with links to a doomsday cult, Officer Chan (Louis Koo) reluctantly enlists police occult expert Officer Chiu (Anthony Wong Chau-Sang) to help him solve the case. But during their investigation of the cult and its charismatic leader The Pope (Hoi Lin), they realize the killings may be related to a previous serial murder case, their own pasts, and the psychotic hypnotists in charge of it all may be preaching some truth…