Dr. Frankenstein and his monster both turn out to be alive after being attacked by an angry mob. The now-chastened scientist attempts to escape his past, but a former mentor forces him to assist with the creation of a new creature.
A novelty-salesman moves his family into a new house. Initially dismissing incidents as more of their father's practical jokes, the family soon learns that the house is haunted by people who lived in the house 300 years previously.
Frankenstein's unscrupulous colleague, Dr. Bohmer, plans to transplant Ygor's brain so he can rule the world using the monster's body, but the plan goes sour when he turns malevolent and goes on a rampage.