Tie san jiao (1972)

Kon Loong, a rickshaw boy, learns kung-fu from master Auyang Tin-Kin, for three years of practice. Kon Loong is recognized as the best among all the students. One day, when the master is out for a journey, another fighting association sends a challenge to the school, and Kon Loong accepts it. He goes with four other brothers, but they are badly defeated by their opponents, who hired the help of a Japanese karate fighter. When the master returns, he will have to save the school's honour, in a duel against the two other schools.