Goofs

When Dr. Namaroff is fighting Paul Heitz at the end of the film Peter cushing (who has a moustache throughout the film) has a double for part of the scene who clearly has no moustache.

When the nurse rolls Sasha's stone body in and hits her finger on the table she breaks off about 2/3 of the finger. Later the finger on the ground and the missing digit is the entire finger.

When Carla meets Heitz in the graveyard, she tosses back the hood of her cape. In the next camera angle, the hood is artfully draped around her shoulders. This occurs again in the castle scene.

Professor Heitz's hairline is entirely different between his early scenes and later ones, after he's been gorgonized.

Megaera is an Erinýe, or Fury, not a Gorgon. The Gorgons were named Stheno, Euryale, and Medusa. The film states that there are two deceased Gorgons, Medusa and Tisiphone. The Erinýes are named Alecto, Megaera, and Tisiphone, and there are no stories of them being killed. The Erinýes had snakes for hair, which may have resulted in the confusion. They are best known from Agamenon's _The Eumenides_, which means The Kindly Ones, a euphemism for the Erinýes, immortals who avenge intrafamilial murder.

In the climactic scene in the castle, during the fight between Namarof and Heitz, Namarof tries to secure his balance by holding on to an iron candlestick which bends, revealing itself to be made out of rubber.

Painfully obvious stunt double for Peter Cushing in the sword fight.

When the Inspector finds Prof. Meister threatening Dr. Namaroff with the knife, he points his gun at Meister to get him to let Namaroff go. When Meister moves out of the way and the Inspector approaches Namaroff, the Inspector continues to point his gun at Namaroff until they leave the room. Any decent law enforcement officer wouldn't point a gun at someone they don't plan to shoot.