It turns out that Henson had a bit of a screenwriting career in the pre-Muppet '60s, specializing in live-action surrealism. After an Oscar-nominated short film and an hour-long drama for NBC, "Tale of Sand" was his feature-length vision for this sort of thing but he was unable to sell it in the early '70s. Once the "The Muppet Show" and Henson's unfortunate early death came along, there was never time to go back to it.
It's hard for me to imagine how this could have been successful as a movie. The main character spends the story being chased across the Western US desert and encountering machine-gun nests, lions, speakeasys, sharks, shieks, and a college football team, just to name a few. Which is great, but to me it never paid off in any significant way. Maybe at the time it was written people were more open to experimental fare, but I don't think it could be made now in sequel-obsessed Hollywood.
|Why is our hero carrying a giant key? I have no idea. Looks great, though.|
To be fair, this kind of surrealist work is highly subjective. Comics Alliance calls Tale of Sand "the best work to come out of Archaia", a distinction I would give instead to Return of the Dapper Men (and, I suspect when all is said and done, Cow Boy), so as we say around here: your mileage may vary.