Idealistic police cadet Chan Wing-Yan (Tony Leung) is recruited by Police Superintendant Wong (Anthony Wong) to go deep undercover as a member of the criminal Triad society. Into the same cadet class, crime boss Hon Sam (Eric Tsang) installs new Triad member Lau Kin Ming (Andy Lau) to become a long-term mole for the gang. A decade later, both have risen through the ranks in their respective aliases -- but when both of their covers are in danger of being blown, a game of life and death ensues.
Director: Wai Keung Lau and Siu Fai Mak
Writer: Felix Chong and Siu Fai Mak
Producer: Ellen Chang, Lorraine Ho and Andy Lau
Cast: Tony Leung, Andy Lau, Anthony Wong, Eric Tsang, Chapman To, Lam Ka-tung, Ng Ting-yip, Wan Chi-keung, Sammi Cheng, Kelly Chen, Edison Chen, Shawn Yue and Elva Hsiao