Le Sceptre d'Ottokar
Comic books contain some other early appearances of evil twins. One example, still available on the market today, is "King Ottokar's Sceptre" by Hergé which originally was published in 1938-39. Tintin is hired as Professor Alembick's secretary and flies with him to Syldavia. The real Alembick has been abducted in the beginning of the story, and unknown to Tintin replaced by an antagonist, in a plan to steal the sceptre. In the end of the story Tintin understands the impostor was the evil twin of the professor.