Narcotics officer Shaolun (Tony Leung Ka Fai), in order to bring down the local drug kingpin King (Michael Wong), forces a female street thug with an equally sketchy past, Coco (Rosamund Kwan) to infiltrate King's organization and provide information. What no one expected was for both men to fall for Coco, and Coco for King.

Three female room-mates fall in and out of love and chase the wrong men. Through their relationships they learn a lot about life, love and their own personalities.

Hiu-tung (Veronica Yip) is a naïve young wife who is forced to raise her child alone after her gangster husband skips town for Taiwan. Her next-door neighbor is Ching-man (Tony Leung Kar-fai), a cop still coming to terms with his partner's sudden, inexplicable suicide. Inevitably, the two begin to find solace in each other's company -- Ching-man even acting as a sort of surrogate father for her son -- and soon in each other's arms. Just as true love seems about to bloom, Hiu-tung's thuggish husband returns.