Kin Shing is the leader of a drug syndicate, code-named "Black Wolf", while his older brother Kin Chung is a member of the Narcotics Division of the Hong Kong Police Force. At the same time, he is involved in a fight against drug lords and it is this investigation that the elder brother discovers that his younger brother had another identity. The two starte a confrontation between good and evil for their respective goals.

• Bosco Wong Chung-Chak
• Michael Tse Tin-Wah
• Joel Chan Shan-Chung
• Cheung Kwok-Keung
• Michael Chan Wai-Man
• Alice Chan Wai