Also known as Shadows over Bridge Farm, Curse of the Dead, Doctor Maniac and even Kill, Baby, Kill, this is a South African/British coproduction that mixes science fiction and horror. Yes, it did just straight up take that Bava title.
It’s also kind of House of Usher, as Lady Brattling wants her family to end, what with her son Michael running the house while his brother Breck (both roles are played by Mark Burns) hides in his room and tries to finish an experiment that creates a physical version of the soul outside the human body. Michael’s fiancée Mary then shows up and wants to start making heirs, all while the help engages in voodoo and a murderer is so close by, starting with animals and soon killing humans.
Director Ray Austin mainly worked in television and also directed Virgin Witch. The script is by Marc Marais (Crash!) from a story by John Brason. They made a movie in which a man operates on monkeys and traps souls in liquid, but put a title on it that promises zombies and does not deliver them. It’s kind of too mannered and needs the kind of director that allows everyone to go insane in the heat of the plantation and scream and wail and collapse into terror, but it never gets there.