Infernal Affairs 3

The epic story of the triads ends as it started; ruthless, cruel and without mercy.
2001: Gangster boss Sam gives mole Yan (Lau), responsibility for a major operation. Yan is nevertheless not acquainted with Sam´s secret agenda, which will put his life in danger. When the operation goes overboard, Yan has to make a fatal decision; risk his life fighting for the boss, or reveal his identity as policeman. 2004: Ming (Leung) has been degraded to clerical position in the police department. At the same time a new star, Yeung, is making a career within the police. Ming is suspicious, and believes him to be a new mole from the triads. This results in Ming starting an investigation to reveal Yeungs secret identity. However, he soon finds himself under the surveillance of Sheng, and a connection between Sheng, the triads and the new comet Yeung manifests itself. By then the trap has already been laid for Yan.