My recent review of Argo pretty much just went on about the fake movie within the movie and its real-life story. I wouldn't have minded a movie just about that amazing unmade movie. Which is pretty much what I got from Jodorowsky's Dune (2013).
Alexander Jodorowski is an odd surrealist filmmaker. I've never seen any of his movies, but his psychedelic Western El Topo was one the the first great midnight cult movies. In the mid-70s, he had a chance to make a movie with a substantial budget, and he picked Dune.
Why he picked Dune is a little unclear - I'm not sure he had even read it. In fact, it's kind of a running joke that no one involved actually read the book. But he threw himself into it with all his heart. He wrote a script. He hired Jean "Moebius" Giraud (The Airtight Garage of Jerry Cornelius) to do storyboards. He got Pink Floyd to do some of the soundtrack. SF paperback cover artist Chris Fosse would do art direction, along with H.R. Giger (Alien). He got commitments from Salvador Dali, Orson Welles, Mick Jagger and David Carradine to play various roles. Dan O'Bannon (Dark Star, Alien) would do special effects. And then it all fell apart. The project passed to David Lynch. None of the material was used.
And yet... The thesis of this documentary is that Jodorowski's Dune inspired a generation or more of cinema - When the detailed storyboard went around Hollywood, it failed to find backing, but it inspired a lot of imitation. This film gives credit for Star Wars and Alien at least to Jodorowski. It sounds pretty far-fetched to me, but it's an interesting idea.
Also an interesting movie. I'm just guessing, but I'll bet Jodorowski's Dune, if it had been made, would have been a worse disaster than David Lynch's. Maybe an interesting cult film like Zachariah, with a tiny audience of rabid fans with low expectations. I think I like it best the way it is, as nothing but a dream, and a damned fine documentary.