The Corsican Brothers (1941)
The Corsican Brothers is a 1941 swashbuckler film starring Douglas Fairbanks, Jr. in a dual role as the title Siamese twins, separated at birth and raised in completely different circumstances. Both thirst for revenge against the man who killed their parents (played by Akim Tamiroff), both fall in love with the same woman (portrayed by Ruth Warrick). The story is based on the novella Les frères Corses (in English: The Corsican Brothers) by French writer Alexandre Dumas, père.
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