- Detector Li Ki (Gallen Lo) is impartial and honest. He likes to eliminate the bullies and help the down-trodden. He is appointed to catch the legendary female gallant "Black Rose". Ki is very depressed as he finds himself being stay idle. He meets his good friends, Tse Yuen (Gordon Lam). Yuen brings Ki to his home - conceals his identity and starts a thorough investigation in "The Art Garden". Meanwhile, he gets to know an amusement performer, Bo Chu (Maggie Cheung) and a chewing gum girl, Fong Fong (Elaine Ng); Ki loves Chu at the first sight. Fong secretly admires Ki. Chu and Ki eventually become lovers. Fong is very upset. Yuen tries his best to suppress his love feeling to Chu because of Ki. Both Fong and Yuen are suffers. Mutual sympathy developed between the two and they gradually fall in love with each other.
Once, Ki discovers the Chu is Black Rose. He is in a dilemma. What should Ki do? Ki decides to conceal the truth. Chu promises that she will not commit crime again. Unexpectedly, the Black Rose again takes action. Has Chu broken her promises? Ki is in a towering anger that he left Chu. Who is the Black Rose? Is she Chu or somebody else?