Sherlock Jr. is a 1924 American silent comedy film directed by and starring Buster Keaton and written by Clyde Bruckman, Jean Havez, and Joseph A. Mitchell. It features Kathryn McGuire, Joe Keaton, and Ward Crane.

Plot

Buster is a movie theater projectionist and janitor. When the cinema is empty, he reads a book on How to be a Detective. He is in love with a beautiful loveable girl. However, he has a rival, the "local sheik". Neither has much money. He finds a dollar note in the garbage he swept up in the lobby. He takes it and adds it to the $2 he has. A girl comes and says that she lost a dollar. He gives it back. But then a sad old woman also says that she lost a dollar, so he gives that also, leaving himself with $1. A man comes and searches the garbage and finds a wallet full of money.