Infernal Affairs II
Andrew LauAlan Mak
Anthony Wong, Eric Tsang Chi-Wai, Carina Lau, Francis Ng, Edison Chen, Shawn Yue, Hu Jun, Roy Cheung, Andrew Lin, Joe Cheung, Henry Fong Ping, Peter Ngor Chi-Kwan, Arthur Wong, Teddy Chan, Chapman To, Wan Chi-Keung, Bey Logan
7.2 from IMDB
In this prequel to Mou gaan dou (2002), Chan Wing Yan has just become an undercover cop in the triads while Lau Kin Ming joins the police force. Both the triads and the police find an enemy in a rival crime boss.