Secret of Chinese Kung Fu (1977)

Two sisters on their way home from a fishing trip spot a mysterious man in the water. After rescuing him from drowning, they learn he's a martial arts master -- a good thing, since a gang of vicious thugs is ravaging the girls' village. Out of gratitude, the man agrees to train the sisters for the fight of their lives in this kung fu adventure from Sung Ting Mei co-starring Byong Yo and Sha Ling Ling.