Chief B (Danny Lee) is an unconventional CID member who relies more on instincts rather than by the book to resolve situations. He's a down-to-earth fellow who's a mamma's boy, not too well-educated, and an outstanding member of the CID. Police Officer Kit (Eddie Chan) has just been promoted from the rank-and-file to CID, and at the same time is studying for the test to become an Inspector. Chief B takes him under his wings to investigate numerous gang-related cases. Kit, previously a by-the-book type of police officer, learns a lot from Chief B.

The real story unfolds two-thirds of the way through the movie, when two tragedies occur, one that Chief B is directly involved with, and one that he had no control over. These tragedies really play on the mind of Chief B and tests his mettle.

Danny Lee won the 1984 HKFA Best Actor award for his portrayal of Chief B in the movie. He was also nominated for Best Director for this movie. This movie was his breakthrough movie and the springboard for his movies later on such as City on Fire and The Killer. He had been an actor for many years in many non-descript roles until this movie.