Description: Set in pre-1997, before the return of Hong Kong to the People’s Republic of China. Chan Kwok-chung (Simon Yam), a Hong Kong police inspector, has dedicated his career to putting Wong Po (Sammo Hung), a notorious triad boss, behind bars. While escorting a witness with damning evidence of Wong’s wrongdoings to court, Chan’s car is rammed at high speed by another car driven by Jack (Wu Jing), a ruthless assassin hired by Wong. The impact severely injures the witness and his wife, whom Jack proceeds to kill after getting down from his car. The witness’ young daughter, however, is spared. Chan survives too, but has a piece of glass stuck in the back of his head. When the glass is removed, the doctor notices a tumour in Chan’s brain and informs him that he does not have long to live. Chan becomes even more determined to bring down Wong Po, using any means necessary.
Three years later, Ma Kwun (Donnie Yen), a police officer from another precinct, is assigned to replace Chan, who is going to retire soon, and take over leadership of Chan’s team, composed of Wah, Sum and Lok. All the three men are very protective of Chan, who has since adopted the slain witness’ daughter.
An electronics shop owner brings to the police station a video tape of Wong Po murdering an undercover agent planted by Chan in the triad. In the video, Wong is seen swinging a golf club repeatedly, allegedly at the agent’s face, but does not kill the latter, and instead allows one of his men to finish him off. Chan and his colleagues decide to alter the tape, intimidate the shop owner into accusing Wong Po of being the murderer, and eliminate the real killer (Wong Po’s henchman, the one caught on tape shooting the undercover agent).
Ma Kwun, who had once beaten up a drug trafficker so badly that the latter has become mentally handicapped, has vowed to abstain from using questionable means in his career as a policeman, unlike Chan and the rest of the team. He is upset when he sees Chan and his colleagues resorting to those “dirty” methods to frame Wong Po for murder. He witnesses Chan and the three men cornering Wong Po’s henchman (the one who killed the undercover agent) and pushing the latter off a building, and confronts the four of them, resulting in a brief fight. Despite their disagreements, Ma still assists Chan and the team later in the arrest of Wong Po, which culminates in a brawl in the lobby of a department store with the rotund crime lord.
The squad receives a warning that all of them will not make it to see the next day if they get out of the police station that night. Ignoring the threat, Lok goes to buy a gun to serve as Wong Po’s “murder weapon”, but is trapped in an enclosed area and ends up getting killed by a knife wielding Jack. Later that night, Jack sneaks up on Wah and Sum and stabs them to death. Ma Kwun rushes there to save them but arrives too late. Before dying, Wah confesses to Ma that he, Sum and Lok had stolen money from Wong Po (when they busted one of Wong’s drug operations earlier) to help Chan raise his adopted daughter, and were targeted for retaliation by Wong. Back at the police station, Wong Po’s men show up and give a copy of the original video tape to Chan’s superior, Cheung Chun-fei. Cheung discovers that Chan had tampered with evidence to frame Wong Po for murder, so he releases Wong and goes to confront Chan. However, with help from an elderly policeman called Uncle Ba, Chan hides inside the washroom until Cheung and the others have left.
Later that night, Chan goes to Wong Po’s office alone to return the stolen money. He attempts to catch the crime lord off guard and shoots a few goons but is eventually overpowered by Jack, who knocks the revolver out of Chan’s hand and then thrusts his knife through it.
In the meantime, Ma Kwun has a heated argument with Cheung over the handling of the case and he turns in his badge and gun. He receives a call from Wong Po, who tells him that he has taken Chan captive. Ma encounters Jack in a back alley. Armed with only a baton, Ma engages in intense martial arts combat with the knife expert. Jack wrestles the baton away from Ma’s hands, but Ma manages to eviscerate Jack with his own knife.
Ma then heads up to Wong Po’s office and sees Chan strung up and unable to move. He fights with the crime lord and seemingly kills Wong when he backdrops the latter onto a tall display of glasses and bottles. Ma sits down at the bar and starts to pour himself a drink. Chan, still strung up, starts to speak to Ma. However, Wong suddenly gets up and throws Ma out of the window. Ma lands on the roof of the car in which Wong’s wife and baby son are in, crushing them, and all three of them are killed instantly. When Wong gazes down at Ma’s body, he notices the car underneath and recognises the number plate. He slumps down and starts sobbing, broken with grief over his actions.
In the final scene, Chan and his adopted daughter are seen on the beach, with the girl playing near the shore. Chan finally succumbs to his tumour and dies