Night of the Ghouls (1996)

Detective Lt. Dan Bradley (Duke Moore) interrupts his opera night to investigate strange sightings of ghosts at a remote farmhouse where a mad doctor had experimented with monsters several years earlier (Bride of the Monster?) Along with him goes faint-hearted patrolman Kelton (Paul Marco). What they find is that fake spiritualist Dr. Karl Acula (Kenne Duncan) is running a spiritualist con game, bilking people into thinking they can contact dead relatives for a hefty fee. Karl's conniving girlfriend Sheila (Valda Hansen) cruises the grounds like a ghost for an undisclosed reason, as well, and the Karl has the goonish, giant Lobo (Tor Johnson, apparently survived from the previous film with gross facial scars) for use as a henchman. As the cops close in on Karl's racket, it becomes clear that there are other ghosts haunting the premises - that aren't Dr. Acula's cheap illusions.