A doctor invites his relatives to his castle, all the while planning to murder them when they arrive. However, when he himself is murdered, the relatives know they have to find the killer before he gets all of them.
Includes: The Awful Dr. Orlof, Dr. Orloff's Monster, The Diabolical Dr. Z, The Orgies of Dr. Orloff, The Invisible Man's Love Life, The Sinister Eyes of Dr. Orloff, The Sinister Doctor Orloff, Faceless
