Mad Detective
Bun, a schizophrenic, former police inspector comes out of retirement to help a rookie detective solve a complex murder case involving a missing colleague and a suspected policeman suffering from a multiple personality disorder.
Sean Lau
Inspector Chan Kwai Bun
Andy On
Inspector Ho Ka-on
Gordon Lam Ka-Tung
Ko Chi Wai
Kelly Lin Hsi-Lei
May Cheung
Karen Lee Choi-Ling
Gigi
Lee Kwok-Lun
Wong Kwok Chu
Eddie Cheung
Violent Man - Ko's Inner Personality
Lam Suet
Fatso - Ko's Inner Personality
Jay Lau Kam-Ling
Calculating Woman - Ko's Inner Personality
Jeff Cheung Ka-Kit
Ko's Inner Personality
Lu Ching-Ting
Ko's Inner Personality
Chiu Chi-Shing
Ko's Inner Personality
Hung Wai-Leung
Ko's Inner Personality
Flora Chan Wai-Shan
May Cheung in Bun's Eyes
Jonathan Lee Yat-Sing
Weak Boy - Ho's Inner Personality
Jo Kok Cho-lam
Schemy Woman - Ho's Inner Personality
Eddy Ko Hung
The Chief
Yuen Ling-To
Policeman
Jimmy Wong
Restaurant Manager
Ronald Yan Mau-Keung
Chi-Wai's Boss
Apple Chow Suk-Wai
7-11 Worker
Jackson Ha Chak-Shun
Ko's Colleague
Jack Lai
Ko's Colleague
Singh Hartihan Bitto
Naresh Sharma
Wong Shiu-Keung
Policeman (uncredited)
Lui Siu-Ming
Mahjong Parlour's Staff (uncredited)
Mark Cheung Yiu-Fai
Mahjong Parlour Customer (uncredited)
Soi Cheang
Inspector Ho Ka-on (voice)
Florence Kwok Siu-Wan
May Cheung (voice)