The details of undercover police officers are deleted from a police database and a senior officer is left struggling to know who are the undercover officers and who are the criminals.
Chief inspector of Hong Kong’s Criminal Intelligence Bureau, Cheuk Hoi, is suspicious of his close colleague’s mysterious death. Adding to the enigma, he discovers that the five undercover agents who were in constant contact with his dead friend have all vanished.
Bao Seed engages in drug trafficking in Thailand. Unaware of Ah Deng's whereabouts, he is shocked to learn that she has died and promises to avenge her. Bao Seed continues with his undercover work under his new superior Madam G. After serving time, Cheuk Hoi is released from prison and opens up a coffee shop, yet trouble continues to follow him in spite of his efforts. Ngai Tak Lai is a cop tracking on Bao Seed's tail. In truth, he is buoyed by an ulterior motive.