A (found animated short film; 1965)
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A was an animated short film created by Jan Lenica in 1965. It was about a writer literally being tormented by the letter "A." Just when he thinks he has gotten rid of it, a "B" shows up and continues to torture the writer. Lenica described it as follows: "It is a very simple film, with only one man and one letter in one set design. It is about a conflict between the man and the letter."
For a long time, the film was believed to be lost, as it was not released on any home media nor uploaded online and only two prints were known to exist. However, on March 27, 2016, the short was uploaded by YouTuber "Namfoodle" via an episode of a 1973 show named Screening Room. The short can be viewed below.