Madam Satan (1970)

Five people, two men and three women, arrive at psychic Madam Cobra's home and are let in and then seated at a table by her slow-talking half wit butler Igor. Blonde psychic Cobra finally shows up promising to give them "an experience you shall never forget." She lays out the pre-seance ground rules (absolute silence, no breaking the chain), smoke rolls and suddenly everyone's sitting on the floor in a circle naked.