In "The Playhouse" Buster Keaton plays all the musicians of a "vaudeville" orchestra, the maestro and the audience. In 1921, that required a type of photographic trickery never tried before. Until then, a double exposure showing a film star on screen two times at the same time (usually in the role of twin brothers) would leave the audience flabbergasted. It was considered a scientific miracle. In this film, operator Elgin Lessley, aided by Fred Gabourie, special effects technician, managed to put on screen nine different Buster Keaton at the same time.