A mad scientist wants to get his hands on a certain growth-accelerating serum developed by Hong Kong scientist Dr. Li Zong-Hua so that he can create an army of supermen and conquer the world.

The bandits of Hulu Valley murder the chief of Mei Clan while searching for a treasure map. In retaliation, the clan’s leading swordsman Feng-chun (Chan Leung) infiltrates the bandit’s fortress hideout in anticipation of a surprise attack by a larger force and unexpectedly finds himself romantically involved with the bandit leader’s feisty daughter (Cheng Pei-Pei).