In realising their scheme to rule the underworld, the Poisonous Snake Gang breeds the 'Blue Poisonous Bees' and sends Red Rose to the Flying Dragon Gang to execute the 'Flying Sting' mission. Chased by Lung King-tin, both of them are captured by Anna Tai of the Female Monster Gang. The three gangs fight for the possession of a nuclear pistol and allegiances shift as the agents fall in love.

Fong Ching-wah (Josephine Siao) assumes the alias of Annie Yuen and works with the police in investigating the homicide of her father Sau-nin, a jeweller. Befriending Lee Yau-sam (Woo Fung), the adoptive son of gangster Lee Tin-fung (Sek Kin), Ching-wah not only wins his trust but also his affection.