Boris Karloff (23 November 1887 – 2 February 1969), whose real name was William Henry Pratt, was an English-born actor who emigrated to Canada in 1909. Karloff is best remembered for his roles in horror films and his portrayal of Frankenstein's monster in Frankenstein (1931), Bride of Frankenstein (1935), and Son of Frankenstein (1939). His popularity following Frankenstein was such that for a brief time he was billed simply as "Karloff" or "Karloff the Uncanny". His best-known non-horror role is as the Grinch in the television special of Dr. Seuss’s How the Grinch Stole Christmas!.

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