The Return of Doctor X (1939)
The Return of Doctor X (also billed as The Return of Dr. X) is a 1939 American science fiction-horror film directed by Vincent Sherman and starring Wayne Morris, Rosemary Lane, and Humphrey Bogart as the title character. It was based on the short story "The Doctor's Secret" by William J. Makin. Despite supposedly being a sequel to Doctor X (1933), also produced by Warner Brothers, the films are unrelated.
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