Sexy Sisters Die Teuflischen Schwestern

—Edna keeps her younger sister Millie drugged and chained to her bed. The drugs have made Millie a nymphomaniac who’s endless supply of men that Edna providers her cannot satisfy her and seeing her sister unsatisfied gets Edna off. But Edna’s main plan from all of this is to inherit her deceased parents’ fortune which is supposed to all go to Millie on her 21st birthday, so if she can prove Millie insane she will get the fortune. But when one of the men appears to satisfy Millie, Millie discovers the outside world and the two will try to stop Edna’s evil plans.
—In a forgotten corner of the Orient, on a wealthy oceanfront estate, the beautiful Countess Edna Von Stein (Pamela Stanford) keeps her younger sister Millie (Karine Gambier), a mentally-ill nymphomaniac, chained up in a room for her own protection. By night, she cruises nightclubs and picks up local studs for sexual encounters at her estate, with either herself, Millie, the servants, or everyone at once. But all is not as it seems. We soon learn that Edna has nefarious designs on her younger sister, who is having strange, sexual hallucinations. What is reality, and what is nightmare, is made appropriately ambiguous—even if Franco does not strictly adhere to Millie’s point of view—thus diminishing some of the tension. Spanish exploitation regular Jack Taylor makes a welcome appearance as the charming doctor who has nefarious designs of his own. His acting is strong, and Franco lets him have fun in the role. The scene where he sticks a thermometer up Millie’s butt while she lies there naked, casually carrying on a conversation with him, is priceless and rather erotic.
—Countess Edna Luise Von Stein keeps her disturbed sister Milly prisoner. Confined to her bed, Milly suffers from a deep sexual trauma resulting from being abused as a child by a muscular gigolo after she had surprised him and her sister in bed. Is Milly incurable, or is that her sister left out of their father’s will and Molly will be the sole inheritor of his immense fortune on her 21st birthday? Edna and her accomplice Dr. Barrios have hatched a plot to have Milly declared insane. Over the years Barrios has been injecting Milly with a drug that has turned her into a nymphomaniac. Milly’s only hope is Joe, the only one of her numerous lovers to have ever succeeded in pleasuring her, who has fallen in love with her. Will he succeed in rescuing her from Edna and Barrios, and will Milly be able to live a normal life?