Wong Jing produces and Cheung Kon-man directs this wacky cop comedy about mismatched partners Fish and Ball (Ng Man-tat and Aaron Kwok Fu-shing, respectively). While occupied with tracking down the thug who cut off Fish's hand, the two are assigned to go undercover and protect Jessy (Deric Wan Siu-lun), the scion of a wealthy businessman under threat from the mob. While posing as Jessy, Ball falls for the lad's beautiful though high-strung girlfriend Jacky (Maggie Cheung Man-yuk) while at the same time trying not to discourage the advances of his ex-ladyfriend Shun (Chingmy Yau Suk-ching).