Duel Personalities is a 1939 Our Gang short comedy film directed by George Sidney.
[1] Upset that his youthful sweetheart Darla has once again thrown him over in favor of neighborhood bully Butch, Alfalfa tries to forget his troubles by watching the free performance by Professor William Delmore, a famed hypnotist.
Chosen as a subject, Alfalfa is hypnotized into believing that he is the fearless D'Artagnan, of Three Musketeers.
Before Professor Delmore can remove the hypnotic suggestion, he is knocked unconscious.
Armed with this bold new personality, Alfalfa not only sweeps Darla off her feet, but also challenges the dumbfounded Butch (Rochefort) to a duel.