When policeman Cha-siu fails to arrest a wanted rapist at a construction site, the suspect's dismembered legs, left arm and torso turn up in three separate locations of the site. Cha-siu commits suicide with an unexplained smile on his face, leaving Inspector Li and his on-the-job girlfriend Peanut to find the missing right arm. The mystery surrounding the case also arouses the curiosity of Balm and Coffee from Moon Weekly magazine. Author Blue who is collecting materials for her new novel also takes interest after giving a tape recorder to a young woman called Ada who has gone blind after watching a horror movie. Their separate investigations come to a dead end - literally - with Balm jumping to his death after meeting the spirit of the dead rapist and Ada stabbing herself through the head with a kitchen knife. Accidentally, Ada's tape recorder is played back at high speed and out of the background noise Blue and Master Li can discern the name of Peanut's grandmother who died 93 years ago...