Police detective Ming (Leon Lai) loses his gun during a drunken binge and attempts to recover it while romancing PR girl Tweedy (Rosamund Kwan). That's the gist of the first two-thirds of the slackly-paced story, which is enlivened by a gun battle, a chase on foot through speeding cars, and comic relief provided by Ming's partner (Ng Man Tat). Things really heat up, though, when Tweedy's old boyfriend Prince (Jacky Cheung), a psychotic killer, comes back to town…