When Mainland Chinese Inspector Zhang runs into the Hong Kong man Cai at the hosital, who has been in a car accident due to chemical poisoning, he immediately senses something fishy about him. It turns out Cai is indeed a drug manufacturer closely linked to the notorious drug lord Li. To save his own neck, Cai agrees to help Zhang arrest Li by facilitating his disguise as a buyer in order to lure Li into a drug deal. Right before this undercover operation is about to bear fruit, Zhang realizes all too late that the relationship between Cai and Li is not what it seems, and instead of having played Cai as a pawn in a battle of wits, he himself has been a pawn in Cai’s own game all along.