Factual error: At the beginning of the intro, the narrator says that the only way to resurrect a vampire is with a sacred rite that can only be performed once a century when the moon is in the eighth house of Aquarius. In Astrology, the eighth house is Scorpio.
Continuity mistake: "The Feverman": Before putting the chain around his neck, the doctor removes both his detachable collar and his black string tie. A few shots later, not only is the collar back, but he's now wearing a red ascot-style tie. Both collar and tie vanish again one shot later. (00:17:05)