LAI is questioned by HANG and MAN PAK-CHU following the sudden disappearance of the fingerprints. HANG and LAI go to the university to consult POK again. Knowing that POK only sees the matter as a fun game to play, LAI gets a little irritated as she will have to rely on his findings and analyses to prove her innocence. POK conducts an onsite investigation, during which he seems to be quite interested in a bundle of electric wires which run through the property office. Inspired by a series of incidents, POK can finally solve the intriguing puzzle. LAI treats POK to dinner at a famous Chinese restaurant, after which they go back home individually. On her way to the MTR station, LAI spots POK eating spaghetti inside a western restaurant. The murderer is finally arrested and HANG offers to treat his staff to a celebration supper……