Rhythm 23 (Rhythmus 23, 1923) is an extension of the same film but with more angles and overlays added, and adding lines rather than adhering to the squares of the original. It looks so similar that the academic argument that both "21" and "23" were made in 1923 looks rather likely. Richter himself at some exhibitions showed these two together as a single film called Un film de Hans Richter. The hand-colored Rhythm 25 (Rhythmus 25, 1925) was the final "chapter," but it does not survive."