The powerful mobster Leung, who is protected by the dangerous and wicked Huan Fai, sells two hundred Japanese weapons and ammunition to a Chinese gang. He uses the smuggler Luy Fu to bring the weapons but the smalltime thief Kim and his gang heist the shipment on the road and dump the cargo into the sea. However, he lures Luy Fu and asks a large amount to return the weapons with the intention of traveling abroad with his brother. Meanwhile Kim befriends Fan Ming, an undercover police office from Shanghai that is investigating the illegal activities of Leung. When the mobster finds that Fan Ming is a policeman, Leung ambushes him and Huan Fai and his men stab the officer that falls from a cliff into the sea. Kim brings Fan Ming's fiancée Ipi Feng to the house of his lover, the prostitute Hung, and tells Ipi Feng that her fiancé was murdered by Leung. She decides to revenge the death of her beloved Fan Ming with tragic consequences.