The murder of the ex-wife of Doctor Sam Charney (Rutger Hauer) leads Detective Della Wilder (Pam Grier) to uncover a series of women's murders somehow linked to a big pharmaceutical company.

Wilder

All the vampires have to take a special potion made by Ghyslain Chabot to be human. Chabot's wife isn't a vampire yet but wishes to become one. Ghyslain doesn't share her desire because of all the rules and responsibilities inherent in being a vampire. As a result, Ghyslain's wife throws him out of the house without the potion.