The Terrifying Man-eating Shark Woman(1980)

Toshio, who works at an architectural firm, visits a fishing port to reminisce about his love with his girlfriend Kyoko, who died suddenly one year ago. On a small island, he meets a woman who looks just like Kyoko. Toshio becomes obsessed with the woman. Soon, a rumor spreads among the fishermen that the woman is the incarnation of a shark.