Hong Kong police agent Cheung (by Aaron Kwok) works undercover in Kangʼs (by Sean Lau) drug cartel. For years, he assists the notorious Thai-Chinese military veteran in operating the syndicate out of South East Asia before moving to Hong Kong.
Following the trail of information left by Cheung, Superintendent Au (by Louis Koo) leads the Narcotics Bureau to bust the syndicate, but Cheung is heavily wounded and saved by Kang in the exchange of fire which follows. The two subsequently hide away in an opium-growing village somewhere in the Golden Triangle. Helped by a local Chinese girl, Noon (by Yang Cai Yu), Cheung is on his way to recovery while Kang bands together with the militia leader Dai (by Lo Ka Leung) to rebuild his narcotics empire.
Out in the remote wilderness, Cheung is cut-off from the outside world, but as soon as he re-establishes contact with Au, the superintendent enlists Interpolʼs help and sets off to the Golden Triangle to bring his fellow back.
On the streets of Thailand, Cheung reunites with Au amidst the shootout unleashed by the law enforcers and members of the cartel, who then informs him of the Thai militaryʼs imminent crack-down on Dai and that he is to revert back to the life of a cop in Hong Kong. However, refuses to leave Noon behind, Cheung hurries back to the lawless village one last time with Au. Word travels fast, and it isnʼt long before Dai receives a tip-off about Cheungʼs betrayal...
What emerges in the frontline of war is a familiar face, but this time, as a friend or foe?
