Naked Ambition (1970)

Wicked woman Ogin is a concubine of a powerful feudal lord Tayu. At first Ogin gains power by poisoning lawful wife of Tayu. To gain more power Ogin let her lover Isogai Iori, kill whoever interrupts her. Film it is based on Jun'ichirō Tanizaki's novel "Kyofu Jidai".