Peter Cushing portrays a collector of supernatural paraphernalia, who buys a mysterious skull from a shady source. The skull is that of the Marquee de Sade and anyone who owns it soon becomes possessed by its desire to kill. Not only that, but the skull can levitate and fly around. Plus, lots of creepy shots from the skull's POV (looking through the skull eye-sockets).Christopher Lee also makes an appearance as a collector of weird objects and warns Cushing to get rid of the skull before it possesses him with its evil. Of course he doesn't listen and he ends up getting killed.