Charlie was now ready to shoot his big pantomime number for two comic actors; this was going to be the climax to the film. He was nervous about it. Charlie would play the violin, his partner the piano. I have read in various books how Charlie discovered the character of the tramp. I was always a bit skeptical. And yet I saw that same process at work when he developed the mad, obsessed violin player for the music-hall sequence. He went into the wardrobe room, tried on different outfits and mustaches, adopted various attitudes in front of the mirror, and slowly I saw a loony violinist emerge before my eyes. Charlie had only prepared a few gags and bits of business for the sequence. He knew he was going to shrink in size (wearing a trick pair of huge trousers); extract the piano’s insides, like a doctor taking the guts from a patient; step onto his violin, and cause the pianist’s music sheets to cascade to the floor. The rest of the scene he would improvise. But Charlie still hadn’t found his partner. […] Then just before shooting, someone told him that buster Keaton was available – that he was also broke, and needed money. That did it. Charlie hired Keaton. […] For the next week, Chaplin and Keaton improvised what became one of the most hilarious comedy sequences ever put on film. […] Keaton scored a great success with the music-hall scene when the film was released. And rightly so. But stories began circulating that Keaton had been even funnier on the set, but Charlie had cut out the best of him. I know this wasn’t so. I was with Charlie during the entire editing of the film; I never left his side. On that sequence, we must have had enough footage to release at least five complete pictures, the problem was weeding out and making sense of the best things in both their performances. Of course, Charlie cut some of Keaton’s gags. If he hadn’t, the picture would have run for ever. But he cut just as many of his own best laughs. Out went a hilarious gag when he shrank into his trick trousers only to shoot up like a giant. I pleaded with him to keep it in. But he said, «You’ve got to keep the narrative going. You can’t stop the picture for this one scene».

Jerry Epstein, Remembering Charlie. The Story of a Friendship, London , Bloomsbury, 1988