Hong Kong Police Supt. Walter Tso arrests Big Dai, the reformed leader of a criminal corporation. When Dai asked his brother Richard Mao to turn himself in to the police, he betrays him and decides to take over the corporation. Dai is imprisoned and an informant is murdered by one of Mao's men. With no evidence against Mao and the corporation, Tso coerced four of the "Five Lucky Stars" to go undercover in the prison, rescue Dai, and help nab Mao and bring down the corporation
Richard Ng Yiu-Hon
Eric Tsang Chi-Wai
Stanley Fung Shui-Fan
Michael Miu Kiu-Wai
Carina Lau Kar-Ling
Lo Hoi-Pang
Joan Tong Lai-Kau
Wong Ching
Walter Tso Tat-Wah
Kenneth Tsang
Elsie Chan Yik-Si
Steve Lee Ka-Ting
Kent Cheng Jak-Si
Wong Jing
Natalis Chan Pak-Cheung
Benz Hui Shiu-Hung
Wellson Chin Sing-Wai
Yu Kwok-Lok
James Ha Chim-Si
Shing Fui-On
Frankie Ng Chi-Hung
Lau Kar-Wing
Ridley Tsui Bo-Wah
Shing Fu-On