猫仔(林国雄饰)与大猫(冼林旭饰)两兄弟，大猫性爱女色；猫仔凶狠阴毒。二人在港，不务正业，终因犯罪入狱。狱中有积犯七叔(罗烈饰)乃黑社会大哥，对猫仔蛊惑和顽强之性格颇为赏识，将之收入门下。左轮泰探长(陈观泰饰)服务警界多年，为人机智，手段强硬，被誉为罪恶克星。当年猫仔兄弟亦是被他拘捕入狱。猫仔兄弟刑满出狱，猫仔欲思报复……

龙蛇混集的小镇上。汪洪为一之首，窝娼聚赌，无法无天，而善长“擒拿手”之王进勇，不甘与同流合污而拒之。一次，王错手打死汪之手下，而逃亡上海。眼看上海之繁华，王决心闯一番事业，虽然困难重重。但经一番苦战后，终成为独一无二的上海滩大亨。

Iron is the son of a rebel leader, but prefers to spend his days gambling and getting into fights. When his father's group is arrested and executed, Iron is forced to flee and hide in the woods as a beggar and thief. After being taken in by a Shaolin monastery and trained in the art of Monkey-Style Kung Fu, Iron vows to hunt down his father's killer and avenge his death.