Rave Fever

Original title: 周末狂熱

Directed by Alan Mak Siu-Fai

A man wakes up with a hangover where his memory should be, and discovers he also has a love bite and a filofax that weren't there before, both of which appear to come from someone named Sonia. In order to return at least one of the items, he attempts to retrace his steps from the night before, through Hong Kong's club culture.