Alex Lee Yip-Kin

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.

Sent into a drunken tailspin when his entire unit is killed by a gang of thrill-seeking punks, disgraced Hong Kong police inspector Wing needs help from his new rookie partner, with a troubled past of his own, to climb out of the bottle and track down the gang and its ruthless leader.