Sins of Desire is a 1993 erotic thriller directed by Jim Wynorski and starring Tanya Roberts.
The film was one of the first of many low-budget erotic thrillers inspired by the success of Basic Instinct (1992) and made primarily for the video market.
It turns out that Monica was investigating the clinic for her boss, private eye Barry Mitchum.
[3] TV Guide thought that the film "provides adequate titillation, helped enormously by the tongue-in-cheek performances of Delia Sheppard and the mischievous Jay Richardson; their randy interplay suggests the patter of a form of sexual vaudeville.
But the forgettable Cassavetes and faded Tanya Roberts are no match for their villainous candlepower, and several scripting sins help destroy this overheated detective story's credibility... Reservations aside, the heavy-breathing set will enjoy this bedroom mystery simply because there is so much activity at the sex clinic.