Plot
In Hong Kong, the Hongmen-descendant and 50,000-strong triad Wo Lin Shing elects a new chairman every two years. The two leading contenders of the current election are Lok and Big D. Lok is calm, patient and even-tempered, while Big D, who attempts to buy the election with bribes, is boisterous, impatient and quick-tempered. After some quarrelling among both candidates' supporters, the triad's elders elect Lok as the new chairman. Big D refuses to honour the result, and instead attempts to obtain the triad's dragonhead baton, the traditional symbol of the chairman's authority, from Whistle, the previous chairman. Whistle orders his driver Four-Eyes to hide the baton in Mainland China. Lok also has his supporters search for the baton.
The police step in to prevent infighting and maintain the peace by arresting the triad's key figures, including Whistle, Big D, and Lok, who is handcuffed and taken away in front of his young son. However, due to a lack of incriminating evidence, the triad members can only be temporarily detained. During the arrest, Big D attacks Whistle, causing Whistle to be hit by a car. A severely injured Whistle indicates intent to testify to the police's anti-triad unit to expose Big D; this extends Big D's detention. Not wanting the triad's crimes to be exposed, Lok has his lawyer convince Whistle to kill himself to ensure Whistle's family's safety. While in custody, the police allow the triad elders to try to broker peace, but Big D threatens to break away from Wo Lin Shing and form a new triad, which would upset triad tradition and bring about much violence; this causes most of the triad to unite against Big D.
Triad members Kun and Big Head, whose bosses previously supported Big D and Lok respectively, are sent to Guangzhou to search for the baton. Mr. So accompanies Big Head and they find Four-Eyes and retrieve the baton. However, mainland police ambush the group, and Mr. So surrenders himself in order for Big Head to get away. Big Head is ambushed and savagely beaten by Kun, but refuses to give up the baton. During his beating, both Big Head and Kun receive calls from their bosses, who have decided to unite against Big D. Big Head gives Kun the baton, who crosses the border and passes it to Jet, a triad assassin. He is pursued by Jimmy, whose triad member uncle and boss were both severely injured by Big D for supposedly costing him the election.
Jet is attacked by Big D's supporters and is severely injured. Jimmy saves him but takes the baton. Despite some initial reluctance, he ultimately gives it to Lok after Lok states that he can improve the triad's earnings. Lok rewards those who assisted him in obtaining the baton (Big Head, Jet, Jimmy, Kun, and Mr. So) with privileges of becoming his godsons. Big D is released on bail after it is paid by Lok. Using the baton, Lok secures his position as the triad's new chairman and offers a deal to Big D. If Big D accepts Lok as chairman, they will take over the lucrative Tsim Sha Tsui area together, Lok will protect Big D's businesses and support Big D for chairmanship at the next election in two years; Big D accepts. The high-ranking triad members, including Lok and Big D, pledge loyalty to each other and the triad during Lok's swearing-in ceremony.
When a rival triad boss, Dinosaur, offers Big D the chance to improve his earnings on the condition that Big D betray Lok, Big D reacts by calling Lok in for an apparent ambush. This is a double cross; Lok and Big D trap and murder Dinosaur. Eventually, Lok and Big D successfully take over Tsim Sha Tsui. During a fishing trip, Big D expresses interest in becoming a co-chairman of the triad along with Lok, pointing out that other triads have such arrangements. Lok responds that this is not their triad's tradition, but Big D does not change his mind. Lok feigns supporting Big D's idea, then murders Big D with a rock; this is witnessed by Lok's son and Big D's wife. She tries to flee, but Lok strangles her to death. Lok buries Big D and his wife and leaves the scene with his shaken son.