The synopsis goes something like this ...
The werewolf Daninsky (Naschy) is sentenced to execution along with Elizabeth Bathory and a number of her fellow witches. Since it is nearly impossible to truly kill him, Daninsky is left in a 'living death', with a silver dagger through his heart and an iron mask to keep him from biting. 200 years later though the dagger and mask are removed and Daninsky returns to activity to fight a resurrected Bathory, who just happens to have a fetish for bathing in the blood of young women.