"Horse's Mouth" certainly stands up well in it's advanced age; at 45 years old it has remained as timeless as any of the great comedic films.
One IMDb writer has tagged Gully as a "vulgar" painter, which goes to show that the sensitivities this film violated are still around. Pinching your loving ex's bum and tickling the rich lady's knee (shades of Groucho), though, are pretty tame today.
Gully Jimson is a rich character, Chaplin-like, who single-mindedly pursues painting while disillusioning aspiring young Nosey about the artist's life. All growled on tiptoes by one of film's classic great actors.
Jimson is a man who's given up all else, including health, wealth, conventional relationships, to live in a leaky houseboat with a vision. But as the story develops it, like all great literature, manages to puncture almost all of life's rationalizing balloons. Jimson is valorized as is Don Quixote, without suggesting that his hero's journey is a painless one.
All is set in a colorful environment with a delightful if conventionally unpolished cast, all the improbably gleeful turns that make the Marx movies so delightful, and a director who contrives seamlessly with Guiness to create a clever and hilarious marvel that can be enjoyed over and over.
Heck yeah, there's even a chase scene! And pull your socks up!
The DVD version includes a short by Pennebaker that feels as fresh and contemporary, accompanied by a Duke Ellington tune, which played along with "Horse's" original release.