Lai-yiu becomes suspicious when Ming-kwan coaxes her into telling him what she knows. Wing-yum goes to the apparel company to proofread some document for Ho-fan. In the process, Ho-fan notices some discrepancy on a delivery note signed by Lai-yiu. He and Wing-yum then go the warehouse to check further. They accidentally discover some drug-tainted apparel. Meanwhile, Lai-yiu puts Ming-kwan into some vehicle that is going to deliver him and the drug-tainted apparel to some industrial building. Ming-kwan is taken to W’s place and also accused of being a snitch. Wing-yum and Ho-fan are caught as Sister Daring recognizes them. Lik-kei deals with Sister Daring by himself. Ho-fan and his chums want to flee. But Lai-yiu is watching them. Lai-yiu takes Ho-fan hostage and brings him to the roof, causing Ho-fan to retrieve certain lost memories. While Lik-kei is confronting Lai-yiu, he realizes she has something to do with his father’s death.
Because of a fatal shooting case, plain-clothes Sergeant Ko Lik-kei runs into a “dull” and “troublesome” witness called Lee Ho-fan. Lik-kei is instructed to protect Ho-fan at all times. Initially, the duo are strangers that cannot stand each other. They then gradually get along. Meanwhile, an apparel company of which Ho-fan is a major shareholder is found to have involved in illicit dealings. Yip Cheung-lok and his son Yip Ming-kwan, who are member of senior management, are associated with these activities. Lik-kei teams up with Ho-fan and Ho-fan’s younger sister Lee Chung-ying, who is a barrister by profession, to investigate. Lik-kei and Chung-ying get entangled in a relationship in the process. Also, Lik-kei’s elder sister Ko Wing-yumand Ho-fan get along sometimes and provoke each other at other times. Fate has brought the foursome together, causing a case that has remained unsolved for more than twenty years to be reopened.
