Two fools learn kung fu from an old master of iron back style. But after getting a beating from the town's hardman they seek out the service of the drunken master to help improve their kung fu skills.

The plot it involves getting rid of the Devil Clan, a gang of very efficient robbers who have never been caught. The depredations must have gotten more blatant because two constables, played by Pearl Cheung Ling and Tin Hok are both tasked with eliminating them. Pearl Cheung recruits Lam Gwong-Wing who is either the third constable of the title or an informant. Lam is a bit of a goof—he would rather lounge in luxury with beautiful young women peeling grapes for him than go after the Devil Clan—which seems to make a lot of sense—but he reluctantly goes along with her after she threatens him. Lam is literally grabbed away from her by the constable played by Tin Hok for his war for his parallel operation. There is a third figure, neither a constable nor a Devil Clanner. He is Wolf Warrior who simply shows up and kills people—lots of people.

John Liu plays himself as the Hong Kong martial films star and son of a NASA scientist kidnapped in Paris whom may be valuable to a criminal organization. Liu comes back to France, where he had a sentimental affair with a Frenchwoman which ended badly and also created the Zen-Kwan-Do martial school. In Paris, Liu must fight many Caucasian top fighters while he looks for his father and daughter.