Inspector Nat (Natalis Chan) send three undercover cops Ray (Chapman To), Tom (Shawn Yue) and Chubbie (Lam Chi-chung) to infiltrate triad boss Sam (Eric Tsang). Sam also sent Watson (Raymond Wong Ho-yin) as a mole to the police force. During their mission, Ray, Tom and Chubbie fall for three beautiful policewoman Angel (Belinda Hamnett), Leila (Race Wong) and Sharon (Iris Wong).