Pi Li Quan plot
A group of Japanese invade a Chinese village and immediately take control. However, the owner of the local martial arts school, who is also a creditable kung-fu fighter, refuses to acknowledge their authority. The Japanese set up an ambush in which he is killed. With the help of some villagers, his little son escapes to the nearby hills where he is captured by a group of rebels. Under the leadership of Gam Kei-Chu, the rebel leader, he is trained in martial arts. Ten years later, he returns to his village, armed with his father's secret technique, the Thunderbolt Fist, in hopes of avenging his father.