The Night Evelyn Came Out of the Grave (1971)

A wealthy English lord is suffering a mental breakdown following the death of his red-headed wife, Evelyn, whom he feared was cheating on him. He tours local bars and dives, scouring for lovely red-heads willing to come back to his decaying castle in the country, where he seduces them, then tortures and kills them. His friend the doctor talks him into marrying again to help heal his slowly-rotting mind, which he does--but are the doctor's orders really what he needs?