Color Me Obsessed

Here's a sequence from Buster Keaton's 1921 23 minute long short called The Play House.  If you look closely, except for the last scene with the stage manager and the workmen, every character in the piece is Buster. He wrote, acted and directed the film, as well as inventing the technique that enabled this sequence to be created in the camera with no special effects. The biggest asset was his camera man and his metronome sense of timing. Cameras at the time were hand cranked. They devised a system which allowed the same piece of film to be isolated by light proof "shutters", so that the same roll of film could be exposed in strips. At one point, there are nine Keatons on stage at the same time, so the film was exposed in 9 segmented strips. This required perfect timing by Keaton as he performed the synchronized parts that had to be flawlessly in synch with the previously exposed portion of the film. The little act where he dances a duet with himself is amazing enough, but almost unbelievable when you realize he performed the routine twice.
He also plays all of the characters in the audience, the little kid, the old lady, the society dame, the old geezer all shot the same way.
Still the ultimate hero of the piece is the cameraman, the human metronome, Elgin Lessley. One slip up by anyone, on any take, would ruin the strip of film and all of the previous work.