Chan Wing Yan, a young police officer, has been sent undercover as a mole in the local mafia. Lau Kin Ming, a young mafia member, infiltrates the police force. Years later, their older counterparts, Chen Wing Yan and Inspector Lau Kin Ming, respectively, race against time to expose the mole within their midst.

In this prequel to the original, a bloody power struggle among the Triads coincides with the 1997 handover of Hong Kong, setting up the events of the first film.

The story revolves around three members of a police surveillance squad conducting an investigation into a financial investment group involved in criminal fraud. The focus of the plot, however, is actually on the three officers themselves who stumble upon an opportunity to capitalize on information they gathered during their surveillance.

A corrupt red oil kingpin enlists the aid of a female police officer to help find his son.

A corrupt red oil kingpin enlists the aid of a female police officer to help find his son.

Roast Pork joins the triad as a young man and ends up becoming a trusted lieutenant of boss Kerosene. However, his true passion is in his successful chain of restaurants, his loving wife, and his two children. So when Kerosene wants to promote his trusted right hand man to the top of the organization as a way to take on his financial debts, it's understandable why Roast Pork would want to refuse. Roast Pork comes up with an intricate scheme with his men that would take himself out of the running, but Kerosene's intervention causes it to fail. When all hopes appears to be lost, lifelong gangster Sparrow is released from jail after serving a 20-year sentence for committing a gang-related murder that earned him a guarantee for the leader spot. However, Sparrow has made his own plans to stay out of the gang, setting off a battle of wits between the two men.

Triad gangster turned corrupt cop Lau Kin-ming goes to dangerous lengths to avoid detection.

Roast Pork joins the triad as a young man and ends up becoming a trusted lieutenant of boss Kerosene. However, his true passion is in his successful chain of restaurants, his loving wife, and his two children. So when Kerosene wants to promote his trusted right hand man to the top of the organization as a way to take on his financial debts, it's understandable why Roast Pork would want to refuse. Roast Pork comes up with an intricate scheme with his men that would take himself out of the running, but Kerosene's intervention causes it to fail. When all hopes appears to be lost, lifelong gangster Sparrow is released from jail after serving a 20-year sentence for committing a gang-related murder that earned him a guarantee for the leader spot. However, Sparrow has made his own plans to stay out of the gang, setting off a battle of wits between the two men.

During the warring period of the three kingdoms, ancient China is in turmoil. To unify the country, general Cao Cao, the real power behind the Emperor, enlists the aid of the greatest warrior in the land, Guan Yu. However, Guan Yu is a loyal friend of Cao Cao's enemy Liu Bei so to persuade the peerless warrior to fight, Cao Cao takes his beloved Qi Lan hostage. After leading Cao Cao's forces to victory Guan Yu sets out with Qi Lan to rejoin Liu Bei. Now Cao Cao has deemed him too great a threat to live, and on the journey he must face all the forces at the Emperor's command sent to destroy him.

When a private eye, a jilted bride and a mysterious stranger join forces to track down an elusive mobster, there's more than trouble in the air.