What was the sequel to Bride of Frankenstein (a sequel itself) and the last in the series to star Boris Karloff as the monster?
Son of Frankenstein: Son of Frankenstein is a 1939 horror film directed by Rowland V. Lee, and is the third entry in Universal Studios' "Frankenstein" series and the last to feature Boris Karloff as the Monster. Bride of Frankenstein: Bride of Frankenstein (advertised as The Bride of Frankenstein) is a 1935 American science-fiction horror film, the first sequel to Universal Pictures' 1931 hit "Frankenstein". Bride of Frankenstein:  As with the first film, "Bride of Frankenstein" was directed by James Whale and stars Boris Karloff as The Monster.
Son of Frankenstein