Lei Li lost his right-arm in a sword duel with the master of a martial arts school, long ago. Now, he is able to defend himself well with just his left arm, and kung fu techniques. That he proves with just the help of his friend Chung-Chieng, when he crosses his path with a beautiful girl in need, Pao Chiao. Even against impossible odds, he will prove a great warrior.
The plot involves patriots during the Sung Dynasty and their attempts to rescue a kidnapped prince from Ching troops who have invaded the north of China. The patriots are led by Ti Lung who recruits a mysterious but seemingly superhuman fighter played by David Chiang to find a way to cross a perilous bridge to enter an impregnable fortress to locate and rescue the imprisoned prince.
Two men, one a businessman skilled in Kung Fu, the other a kickboxer discover they are brothers, and together, both in and out of the ring, they must face a crime syndicate. One of the first films to use the martial art of Muay Thai.
