The film tells the story of the collusion between Hong Kong police and gangs in 1973, under the instigation of the British, embezzled huge profits and poisoned the citizens. The Governor of Hong Kong established the Independent Commission Against Corruption. The first two prosecutors were the black and white evil spirits (played by Gu Tianle and Lin Jiadong) who went through countless hardships to investigate the story of Chief Hua Inspector Xu Le (played by Wu Zhenyu) and the lame Hao (played by Leung Ka-fai), who had power in both sides, and finally brought the two to justice.