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
as Tai Shan / Sandy
as Lo Han / Roundhead
as Rhino / Rawhide
as Cone / Pagoda
as Banana Tso
as Big Dai
as Mina
as Richard Mao
as Inspector Tso
as Uncle Kin
as Wife of Lok Gymnastic's boss
as Ting
as Sgt Cheng
as Sgt Wong
as Sgt Chan
as Hung
as Mao's thug
as Boss of Lok Gymnastic
as Mao's Thug