Sean Lau Ching-Wan as Inspector Chan Kwai Bun

Andy On as Inspector Ho Ka-on

Gordon Lam Ka-Tung as Ko Chi Wai

Kelly Lin Hsi-Lei as May Cheung

Karen Lee Choi-Ling as Gigi

Joseph Lee Kwok-Lun as Wong Kwok Chu

Eddie Cheung Siu-Fai as Violent Man - Ko's Inner Personality

Lam Suet as Fatso - Ko's Inner Personality

Jay Lau Kam-Ling as Calculating Woman - Ko's Inner Personality

Jeff Cheung Ka-Kit as Ko's Inner Personality

Lu Ching-Ting as Ko's Inner Personality

Chiu Chi-Shing as Ko's Inner Personality

Hung Wai-Leung as Ko's Inner Personality

Flora Chan Wai-Shan as May Cheung in Bun's Eyes

Jonathan Lee Yat-Sing as Weak Boy - Ho's Inner Personality

Jo Kok Cho-Lam as Schemy Woman - Ho's Inner Personality

Eddy Ko Hung as The Chief

Yuen Ling-To as Policeman

Jimmy Wong as Restaurant Manager

Ronald Yan Mau-Keung as Chi-Wai's Boss

Apple Chow Suk-Wai as 7-11 Worker

Jackson Ha Chak-Shun as Ko's Colleague

Jack Lai as Ko's Colleague

Singh Hartihan Bitto as Naresh Sharma

Wong Shiu-Keung as Policeman (uncredited)

Lui Siu-Ming as Mahjong Parlour's Staff (uncredited)

Mark Cheung Yiu-Fai as Mahjong Parlour Customer (uncredited)

Soi Cheang as Inspector Ho Ka-on (voice)

Florence Kwok Siu-Wan as May Cheung (voice)

Peter Chan Bei-Dak as Cameo (picture in police file)