Chan Wing Yan, a young police officer, has been sent undercover as a mole in the local mafia. Lau Kin Ming, a young mafia member, infiltrates the police force. Years later, their older counterparts, Chen Wing Yan and Inspector Lau Kin Ming, respectively, race against time to expose the mole within their midst.
Andy Lau Tak-Wah
Tony Leung Chiu-wai
Anthony Wong Chau-Sang
Eric Tsang-Chi Wai
Kelly Chen
Sammi Cheng
Edison Chen
Shawn Yue
Elva Hsiao
Chapman To
Lam Ka-Tung
Berg Ng Ting-Yip
Wan Chi-Keung
Chaucharew Wichai
Dion Lam Dik-On
Tony Ho
Courtney Wu
Hui Kam Fung
Au Hin-Wai
Lee Tin-Cheung
Victy Wong Yin-Keung
Yiu Man-Kei
Benjamin Yuen Wai-Ho
Wong Chi-Wang
Addy Sung Gam-Loi
Cheng Wing Yee
Mak Wai-Gok
Kui Mei-Yee
Tam Kon-Chung
Che Jan-Bong
Chin Yiu-Wing
Ho Chung-Wai
Simon Yu Sai-Tang
Wong Kam-Hung
So Wai-Nam
Lai Chi-Wai
Leung Ho-Kai
Terry Lee Ji-Ming
Alex Lee Yip-Kin
Chow Pok-Foo
Hui On-Tat
Ho Wing-Ning
Lee Wah-Chu
Simon Cheung Yuk-San
Leung Chiu-Yee
Chang Kin-Yung