Featuring Alejandro Jodorowsky. Rated PG. In English, French, Spanish, and German, with English subtitles.

What if Stanley Kubrick had directed Ishtar? Or Federico Fellini had taken on Howard the Duck? Alejandro Jodorowsky doesn’t exactly belong in that exalted company, but David Lynch’s Dune certainly has stood the test of time in the major-bomb department. And when something is bad enough to gain a cult following—sandworms and all—that can fuel the kind of what-if speculation adding to its weird lustre.

In this case, the musing has a solid foundation, because said filmmaker, born in Chile 85 years ago and based in Paris after years of doing experimental theatre in Mexico City, came close to completing his own, psychedelically irreverent version of Frank Herbert’s sci-fi classic, a decade before Raffaella De Laurentiis gave it to Dave to desecrate.

Still best known for his beyond-trippy midnight movies El Topo and The Holy Mountain, Jodorowsky attracted some major talents in the preproduction stage. The emphasis was on storyboarding, which is what remains of his work with artists like Switzerland’s H.R. Giger, American Dan O’Bannon, and the French cartoonist known as Moebius. The latter two died recently, as have all but one of the cast leaders he gathered: Mick Jagger, Orson Welles, David Carradine, and Salvador Dalí (as, fittingly, the Emperor of the Universe). But everyone’s presence is strongly felt in Frank Pavic’s curiously inspiring documentary, which leans heavily on powerful images collected at the time.

We can never really know how close Jodo came to making his magnum opus in the pre–CGI era, or if it would have been any good. Highly animated in his recollections, the white-haired maestro—who says he wanted the film to be “12 or 20 hours” long—consciously courts controversy. Hell, his last name is pronounced at least seven different ways by the participants, who now aver the unfinished project’s influence on Star Wars, Alien, and much that came after. The talking heads include his original producers, and son Brontis Jodorowsky, who spent two years training ruthlessly for the tale’s most Christ-like role, until their Dune collapsed. “I would have cut off my own arms to make this movie,” says his father—limbs notably still intact.