After solving a hostage crisis in a kindergarten with her partner Ada, Agent Chen Xiaohong leaves for Scotland. In Hong Kong, the Rifuda Group’s boss Zeng Jian, [Kenneth Tsang], returns after seven years in Thailand and wastes no time hunting down Bin, whom he blames for forcing his exile. Bin attempts to kill Zeng Jian, but is himself killed first by Zeng Jian’s enforcer, Miss Nishiwaki [Michiko Nishiwaki]. With Bin gone, Zeng Jian disperses Bin’s wealth among four generals—Rong, Tiedeng, Paowangbiao, and Fatal Xiong—and the police quietly watch, convinced that one of these lieutenants will step up to lead the organization now that Bin is dead. The authorities also become curious about the enigmatic figure known only as “Sawa Da,” a name they infer from his Thai passport records.
Meanwhile, a civilian named Carrie [Carrie Ng Ka-Lai] is taken hostage at a bustling mall by two machete-wielding thieves. Her police commissioner husband Jin Zhiyuan acts fast to stage a rescue, saving Carrie but suffering injuries in the process.
Ada’s informant Mei warns that Sawa Da will appear at Club Xingda that same night. At a party there, Zeng Jian strikes a deal with Leung Ming to obtain drugs at a furniture warehouse at 9:00 p.m. on Friday the 13th. Zeng Jian tries to reconnect with his old love, Carrie, who has since moved on and is now married to Jin Zhiyuan. Introducing himself as “Sawa Da,” Zeng Jian stakes his claim.
Ada confronts him at the party, revealing his true identity. Mei informs Ada about the drug deal and a police raid that erupts into a violent clash, during which Ada kills Zeng Jian’s right-hand man. Jin Zhiyuan later gambles away more money at one of Zeng Jian’s gambling dens, deepening his debt and giving Zeng Jian leverage to pressure Carrie into sex for money. Jin agrees to trade seized merchandise to erase his debt, triggering a confrontation between him and Carrie. Ada witnesses Jin’s meeting with Zeng Jian and pleads with him not to shoot, but Jin is shot. Carrie is taken captive as Ada is seized and forced into heroin addiction.
Chen Xiaohong returns to duty and learns from Director Huang that the police suspect Ada killed her cousin. Carrie tries to help Ada, but Miss Nishiwaki closes in, killing Carrie as Ada escapes. Mei tries to assist Ada in recovering from withdrawal, but is murdered by Nishiwaki and other thugs. Ada and Mei’s allyship leads them to Chen Xiaohong, and together they plot to topple Zeng Jian’s operation. They infiltrate Zeng Jian’s house, where he is finalizing a deal with Samak. As Zeng Jian attempts to flee, Ada clings to an overhead power line in pursuit. Zeng Jian fires at her, but she manages to reach down, slit his throat, and bring his car to a wrecking finale. The powerful chase ends with Zeng Jian dead and Ada dying on the power line, closing a brutal, intertwined struggle for control and vengeance.
