Koryu heads to Yokohama in search of a woman named Birei, kidnapped by diamond smugglers who move their hot rocks by surgically implanting them into the nubile buttocks of Chinese prostitutes. Koryu's older sister, working as a jewelry designer, is secretly, if unhappily, involved with the gangsters.
Sister Street Fighter: Hanging by a Thread is a Japanese martial arts directed by Kazuhiko Yamaguchi and starring Etsuko Shihomi. The film is a sequel to Sister Street Fighter. It was followed by a third and final film titled The Return of the Sister Street Fighter (1975).
