My guess, based on my own experience watching it in my teens, is that if you are not familiar with the book, you won’t like the movie. it made no sense to me then as i hadn’t read the books. still confusing to this day, it’s crap 😋
i read the book after i watched the film. I will admit that one of the reasons that i so liked that film, is that i watched it in a small-ish theater, which had maybe 20 people on it, at the perfect distance from the screen, so it really was the best experience i could have gotten out of it. And i was young.
According to the release date i would have been 12yo, but i remember being around 14, so possibly a re-issue. Or maybe i dont remember correctly and i really was that young.
Keep in mind that two years earlier, special effects guy Carlo Rambaldi had worked on E.T. (1982), so THIS

is what we conceived of as "incredible special effects".
When i watched the film, eh, i think i pretty much figured everything just from the first viewing. i
n italics the parts that come from the book only.
Paul has been birthed "illegaly" by the concubine Jessica, of the Bene Gesserit. The discussion with her reverend mother makes it clear that she was to follow with the BG's plan of conquest; and Paul is no Kwisatz Haderach.
The Emperor's plan is pretty much laid bare in one of the very first scenes. Kill the Atreides because they are becoming too popular, and "they have a new weapon".
The book explains that House Corinno holds the Golden Lion Throne because they own Salusa Secundus, the prison planet where the Sardauker are trained, therefore the guy with the most ferocious army gets to be in charge; if the weirding modules give normal fighters melee capabilities closer to the Sardauker, then the Emperor wouldn't have as much power, AND the Atreides are in general a lot nicer as people.
Besides, the Harkonnen hate (
their cousins) the Atreides, so they are very happy to help with the plan.
The Emperor and the Harkonnen can't just attack the Atreides together because of the history of the War Of Assassins, the Butleran Jihad, the creation of the Landsraad; essentially the status quo is that, because we've fucked up immensely before, now we have prohibited a whole bunch of things, like atomic weapons, thinking machines, assassin technology (such as the hunter-seeker),
and the Houses are not meant to attack one another, outside of very strict rules of engagement. These restrictions make attacking the Atreides on Caladan both difficult, and illegal in the eyes of the Landsraad; since the Throne is elective, the Houses can chose to just kick the Emperor in the ass at any time.
At least a portion of this is made clear during the two conversations between the Spacing Guild and the Emperor; the threatening language they use makes it clear that the Throne is not the ultimate power in the Galaxy.
When united, CHOAM, the Landsraad, and the various Guilds, hold more power than the Throne.
Paul is introduced and he's shown to be a smart guy, capable, but someone who feels he doesn't fully fit. The Gom Jabbar test shows that he's mentally capable, but not a risk for the Bene Gesserit. He's also told, sideways, of a prophecy involving him. His father Leto, Duke Atreides, believes he can in fact be the Kwisatz Haderach, but Paul doesn't understand the meaning behind the phrase "the sleeper must awaken".
The Weirding Modules are shows as the Protagonist Superpower that makes the hero better than everyone else.
The Atreides settle on Arrakis, and through the treachery of Doctor Yueh they are wiped out by the Harkonnen. Paul and Jessica are thrown to the desert, in a clear example of "take them away and kill them" trope, and they run into the Fremen.
The reason why they are not killed outright, and are shown so much support, is that the Bene Gesserit have for centuries been seeding religious doctrine in every world, inserting the concept of the Kwisatz Haderach / Mahdi / Saviour into every primitive religion, so when they finally succeed in creating said Kwisatz Haderach - whom they expect to have under their control - then every world will have this mythological figure in their religion, thus allowing the Bene Gesserit to control the entire universe.
They (also) show the Fremen how str0nk they are, and since the Fremen have been under the yoke of the Harkonnen for generations and they fucking hate them, the gift of the weirding modules, and/
or the weirding way, is a godsend.
To Paul, the incredible fighting strength of the Fremen is the godsend, as he would otherwise have no way to match the power of the Sardauker troops.
Paul is exposed to spice and has a vision; he risks the Water Of Life and succeeds, becoming the Kwisatz Haderach. Now that he is all-powerful he kicks the butt of the Harkonnen, the Sardauker, and the Emperor AND the Landsraad (
since they ALL need spice, be it for space travel, be it for living longer, or to sustain their various mental abilities, since the book implies that other Guilds exist and that Guilds are based on "superpowers, but of a natural kind"). He marries Irulan (and who wouldn't, she's got a massive rack) and ascends to the Golden Lion Throne as Padisha Emperor Paul Atreides I.
**********
The scene with the guild navigator floating in the spice gas cloud inside the Highliner was already bad in the 80s; i won't defend this any more than just saying, "we used to look past a single bad special effect or two back in those days". It's bad, but it doesn't ruin the mood of the film. It's not like you have a jumpscare in a horror film but the costume of the monster is so horrible that it becomes a joke instead of a scare, it's just a .. it's just a bad special effect. Have you guys ever seen TRON ?? Dude. Tron. You reeeeeaally need to susped disbelief when you watch that film. Don't get me started with Lawnmower Man or whatnot.
But otherwise, i found it a perfectly capable film, and the plot was fully clear to me from the first time i watched it. There is no part that's found
in the book that is necessary to understand the parts that are in the film.
Also, i absolutely LOVED the sets and costumes. The spaceships look real, even the gay gold spaceship the Emperor travels on. You gotta understand that the universe where this film takes place is completely fucked, they have had millennia of barbarism, and people are just not well in the head. That's why Rabban drinks the blood of a live creature instead of a can of coke. People will complain about the idea that Baron Harkonnen forces his workers to get a heart valve installed "so it's easier to kill them for fun" but then glide over his book description of "having a penchant for pederasty and torture". I'm sure it was just diet torture, the nice kind of torture, not the BAD torture, no.
I've hear people complain about the fucking anti-gravity he uses, as if that wasn't in the book.
Herbert writes in
Dune that the Baron possesses a "
basso voice" and is so "grossly and immensely fat" that he requires
anti-gravity devices known as
suspensors to support his weight.
[10][11][12] He is one of the wealthiest members of the Landsraad and a bitter rival of
Leto Atreides,
[13] and the Baron's "legendary evil and intellect" are unmatched by anyone else from House Harkonnen.
[10] In the novel, the Baron feigns outrage over losing control of Arrakis to Leto, but is actually conspiring to use the situation as an opportunity to destroy House Atreides once and for all.
[13][14][15]
William Hughes of
The A.V. Club describes the Baron as "a decadent, monstrous gasbag of depravity and evil".
[16] As ruthless and cruel as he is intelligent and cunning, the Baron is "crafty and power-hungry" and has a talent for manipulating others and exploiting their weaknesses
[11] as well as a propensity for torture and blackmail.
[17] IGN describes the character as "cruel, sadistic, and hedonistic".
[13] Travis Johnson of Flicks.com.au says that Harkonnen is written as "a predatory homosexual given to pederasty and incest, an unrepentant rapist and murderer."
I guess people may just find the weirdness confusing, like "why do the spacesuits look like BDSM gear, why does every interior look like it's from the 1800s, why do they use swords in space" which is understandable, because you need to extrapolate the answer to these questions from what you see in the film, often in small detail. But that's just a nice way of saying "dumb people don't get it", let's be real.
Dune 1984 is
disgusting. The world is corrupt, bloated, vile, it's a hymn to drugs, a triumph of violence.
Dune 2021 is clean, sterile, HEROIC, and fucking bland. If it was a spice, it would be salt.