What's a horror film without Boris Karloff? Boris, the greatest film monster actor of all time, takes center stage in this menagerie of horrors that spins out shock after shock. Like a deadly potion bubbling with eerie mansions, secret experiments and a warning never to look in the basement, this is pure haunted-house hokum all the way! A mad English scientist (is there any other kind?) entertains a young American visitor, serving up tea, terror and a terrific-looking daughter - who is soon torn between her father's evil ways and her need to protect the man she loves from a diabolical end.