Months after the events of the original film, Ming suspects a police superintendent as being a new mole for the triads, while years earlier, Yan embarks on his first mission.
"Unlike “II,” which focused more on the mechanics of duty and honor among crims, “III” returns to the atmosphere of mutual suspicion on both sides of the fence" - Variety
"You probably know the extent to which Asian cinema has influenced the work of Quentin Tarantino. Proving that the exchange of pop-cultural parts works both ways, Wai Keung Lau and Siu Fai Mak’s Infernal Affairs trilogy could be the incestuous syllabus for “The Effects of The Godfather, Michael Mann, Tony Scott, and the American Police Procedural on Asian Cinema.” - Slant.com