Hollywood studios would only let Alejandro Jodorowsky make the film provided that it would be 1h 50 mins long. Jodorowsky declined, reportedly stating that he wanted to make approximately a 15 hour long film. This is a common misconception- he never planned that the actual movie was going to be 15-20 hours, he made this statement in a fit of passion that his artistry would not be confined or compromised by a running time restriction (the studios were asking for 90-120 min running time for profit reasons) asserting that he will make the film as long as he wants it to be, and not because some suit wants more money. While the "Dune Book" being a massive tome; held a script, a full storyboard, and numerous conceptual designs and art work with a budget breakdown it's easy to assume and misconstrued that the finished product would have been over 12 hours.
Alejandro Jodorowsky had originally planned on filming Dune in the early-'70s, setting out to make "a [world-changing] prophet of cinema", a film that was both religious experience and an LSD trip printed onto celluloid. He enlisted the help of Jean 'Moebius' Giraud (Moebius), Chris Foss and H.R. Giger for the visual designs, and Dan O'Bannon to create the special effects. Salvador Dalí was enlisted to play the part of the Emperor, and Jodorowsky also intended to cast his own son Brontis Jodorowsky as Paul, David Carradine as Duke Leto, Orson Welles as the Baron, and Gloria Swanson as the Bene Gesserit Reverend Mother. The soundtrack was to be done by Pink Floyd, whose compositions would represent the progressive House of Atreides, and influential 70s French progressive rock band Magma, whose compositions would represent the evil House of Harkonnen. However, every Hollywood studio that was approached balked at the movie's estimated length (13-14 hrs), but especially the $15 million budget that Jodorowsky insisted on ($8 million was considered big budget in those days). According to Jodorowsky, "The project was sabotaged in Hollywood. It was French and not American. Their message was 'not Hollywood enough'. There was intrigue, plunder. The storyboard was circulated among all the big studios. Later, the visual aspect of Star Wars: Episode IV - A New Hope (1977) strangely resembled our style. To make Alien (1979), they called Moebius, Foss, Giger, O'Bannon, etc. The project signaled to Americans the possibility of making a big show of science-fiction films, outside of the scientific rigor of 2001: A Space Odyssey (1968). The project of Dune changed our lives."
This unmade film would have marked the only on screen appearance of the character Lady Margot Fenring. Despite being a high ranking Bene Gesserit and part of their machinations in Herbert's novel, the character was entirely omitted from the David Lynch film. Her role in the story was taken by Princess Irulan in the SyFy Channel miniseries version. Margot's husband, Count Hasimir Fenring, also had a significant role in Jodorowsky's script, only to be omitted entirely from Lynch's film. Unlike his wife, he did appear in the SyFy miniseries, but in a substantially reduced role from his one in the book. Lady Margot Fenring finally appears in Denis Villeneuve's 2024 adaptation, Dune: Part 2 whereas her husband was cut entirely.
Mick Jagger is one of two famous music artists linked to the role of Feyd-Hautha Harkonnen. Sting portrayed this role in Dune (1984).
Considered by many to be 'The Greatest Film Never Made'. Its lasting impact on Hollywood made it ironic that it never got made, simply because the project's ambition seeped into films like Star Wars and Alien; in a way the film never being made left a bigger impact than it being made in the first place. Jodorowsky's Dune is like other productions like Superman Lives and Justice League: Mortal that got so far into pre-production only to have everything fall apart before the cameras actually started rolling.