The Slavers (1984)

Jim Carmody responds to a newspaper ad concerning a reward for information on the whereabouts of a missing woman, Sharon Dalby. Jim eventually comes to discover that Sharon has been kidnapped by a deranged Professor and his sexually deviant assistants and is being held captive in a remote country retreat. The Professor has developed a scheme whereby young women are kidnapped, raped and tortured, subjected to drugs and subsequently brainwashed to obey commands before being sold for sexual slavery.