The Dead Woman's Footsteps (1986)

Flora is married to Orestes but is also having an affair with Paris. When Flora discovers that she is pregnant by Paris, she decides to notify her twin sister, Zanna, who lives in Paris, to come to Greece. Her goal is for Zanna to take her place so that Orestes won't find out. However, Zanna, who is involved in black magic, is determined to take not only her sister's place temporarily, but her entire life. She kills Flora and claims her husband, her property, and her lover...