When is a failure not a failure? This isn't a riddle or a trick question, but rather the unique scenario we're compelled to ponder while watching Jodorowsky's Dune -- a fascinating documentary probing what some consider to be the most influential movie never made. Conceived before Star Wars made sci-fi a cultural phenomenon and involving some of the greatest artists of the era, Alejandro Jodorowsky's ambitious adaptation of Frank Herbert's seminal space fantasy would have been a film unlike anything that had preceded it on the silver screen. Sadly, the visionary approach that would have made such an undertaking so singular was, in essence, also the very thing that ultimately prevented it from ever going before the cameras -- a tragedy for the creative process and a sad reminder of how heavily Hollywood relies on formula. With the release of El Topo (1970) and its psychedelic follow-up The Holy Mountain (1973, for which he used the name Alexandro Jodorowsky), Jodorowsky became not only a pioneer of psychedelic surrealism in film, but also the father of the "Midnight Movie." Following the success of those two projects, the Chilean director began focusing all of his energies on translating Dune to the big screen. The movie was to star Jodorowsky's own son Brontis along with a stunning cast that included Orson Welles, David Carradine, Mick Jagger, and Salvador Dali, with Pink Floyd providing the score, and art direction by H.R. Giger and Jean "Moebius" Giraud. Two years into the massive production, however, the film was suddenly and unceremoniously cancelled. Yet even today, numerous relics of that ambitious production -- including thousands of enticingly vivid storyboards -- still exist. Early in Jodorowsky's Dune, director and ardent Jodorowsky fan Nicolas Winding Refn (Drive) speaks of visiting Jodorowsky in his home and being taken aback when the director asked him, "Would you like to see Dune?" Enticed, Refn sat down with his idol, who then opened one of the production books originally used to pitch the project to studios, and proceeded to narrate the entire feature in captivating detail. This is likely the closest anyone will ever come to experiencing Jodorowsky's version of Dune firsthand, and even when the director speaks about the production in this documentary -- nearly 40 years after the fact -- his passion is palpable. In conducting extensive interviews with Jodorowsky, filmmaker Frank Pavich allows us a rare glimpse inside of a mind that is constantly creating. A consummate storyteller, the Chilean director offers detailed insight into the trajectory of his career as well as the doomed project. Additional interviews with Brontis Jodorowsky, producer Michel Seydoux, Diane O'Bannon (widow of Dune contributor Dan O'Bannon), H.R. Giger, and Star Wars producer Gary Kurtz, among others, illuminate not only what it is like to work with the mystical-minded director (who affectionately refers to his collaborators on the movie as "spiritual warriors"), but also the factors that made the project so attractive to the artistic pool Jodorowsky assembled as well as the technological limitations of the era. All the while, the camera continually cuts back to Jodorowsky, whose obsession with the undertaking and its philosophical themes is still quite evident. In order to provide some context, Pavich mixes in conversations with a variety of fans, supporters, filmmakers, and journalists, including Richard Stanley, Drew McWeeny, Devin Faraci, and, as previously mentioned, Refn. As compelling as it is to hear Jodorowsky describe the project in his own unique terms, these additional interviews serve as an entertaining and informative means of keeping the story of the unfinished film moving along, and highlighting the ways that it influenced everything from Alien to Flash Gordon to The Matrix. The fact that Jodorowsky's work was such an incredibly influential undertaking despite never making it past the pre-production phase is wholly unique in the world of cinema, and a true testament to the power of the director's vision. When we talk about influential movies, there's typically one distinguishing trait that binds them together -- they were actually produced. The magic of Jodorowsky's unseen Dune lies in the film's ethereal nature; on one hand it's a crime against cinema that the project never came to light, on the other, every fan of the fantastic will be grateful for the legacy it left behind, even in its unfinished form. Watching Jodorowsky's Dune offers testament to both that incredible legacy, and reminds us that cinema can be as much a tool for expanding our consciousness as it is a means of selling concessions.