A woman and her three best girlfriends decide to go off on a weekend away from their husbands and boyfriends, one of them unknowingly under the spell of their hypnotherapist, who then pays the women a visit in their remote cottage, brainwashing each girl in turn before an orgy, after which they are total disciples to him.
yes please
Something different makes each of the four women tick, and the hypnotist quickly susses out what it is for a particular woman and uses it to take her down. And yes, the hypnotist takes down the stalking horse too, because it is so much fun.