






Dr. Laurence, a once-respectable scientist, begins to research the origin of the mind and the soul. The science community rejects him, and he risks losing everything for which he has worked. He begins to use his discoveries to save his research and further his own causes, thereby becoming ... a mad scientist, almost unstoppable.
Acting
Karloff's unhinged transformation from pathetic to terrifying.
Practical Effects
Gloriously creaky brain-swapping machinery and fog machines on overdrive.
Writing
Snappy pre-Code dialogue that doesn't waste a single minute.

Director
Robert Stevenson
Trivia, insights & behind the scenes