Trama

In the year 10191, when faster-than-light travel is possible, and almost all the planets in the known universe are colonized, Duke Leto (Oscar Isaac) of House Atreides, ruler of the ocean planet Caladan, is assigned by the Padishah Emperor Shaddam Corrino IV to replace House Harkonnen as fief rulers of Arrakis. Arrakis is a harsh desert planet and the only source of "spice", a valuable substance that bestows its users heightened vitality and expanded consciousness. Harkonnens have ruled Arrakis brutally for 80 years, and become rich by harvesting Spice, but have unable to quell the rebellion of the native Fremen.

The spice is critical for interstellar travel as it allows Spacing Guild Navigators to use a limited form of prescience to safely navigate interstellar space. In reality, Shaddam intends to have House Harkonnen stage a coup to retake the planet with aid of the Emperor's Sardaukar troops, eradicating House Atreides, whose influence threatens Shaddam's control.

Leto is apprehensive but sees the political advantages of controlling the spice planet and forming an alliance with its native population, skilled fighters known as the Fremen. Fremen consider spice a sacred herb and see the occupation of their planet as oppression. Leto knows that emperor wants war between Atreides and Harkonnen and has ensured it by giving Arrakis to Atreides.

Leto's concubine Lady Jessica (Rebecca Ferguson) is an acolyte of the Bene Gesserit, an exclusive sisterhood whose members possess advanced physical and mental abilities. As part of their centuries-long breeding program, the Bene Gesserit instructed Jessica to bear a daughter whose son would become a male Bene Gesserit called the Kwisatz Haderach, a messianic super-being with the clairvoyance necessary to guide humanity to a better future; instead she bore a son, Paul (Timothée Chalamet).

Throughout his life, Paul is trained by Leto's aides, Duncan Idaho (Jason Momoa), Gurney Halleck (Josh Brolin), Suk doctor Wellington Yueh (Chang Chen) and the Mentat Thufir Hawat (Stephen McKinley Henderson), while Jessica trains Paul in Bene Gesserit disciplines. Paul confides in Jessica and Duncan that he is troubled by visions of the future. Because of these visions, the Reverend Mother Gaius Helen Mohiam (Charlotte Rampling) visits Caladan and subjects Paul to a deadly test to assess his impulse control (she subjects him to immense pain and threatens death if he withdraws from the test), which he passes.

Mohiam tells Jessica that she broke the rules by bearing a son and then training him in Bene Gesserit. She says a path has been laid out for Paul and hopes that he doesn't die on the same. Jessica tells Paul that for thousands of years the Bene Gesserit has been cross breeding bloodlines to generate a human capable to bridging the space time continuum, a person who can bring together the past and the future, known as "the one". Paul is a prospect. Paul wants to go to Arrakis with the advance party, but Leto is against this since Paul is the future of the house of Atreides.

Mohiam instructs House patriarch Baron Vladimir Harkonnen (Stellan Skarsgård) to spare Paul and Jessica during his coup, to which he Duplicitously agrees.

House Atreides arrives at Arrakeen, the fortress stronghold on Arrakis, where Duncan and an advance party have been learning about the planet and the Fremen. The freemen already see Paul as "The One" and regard him as such. Paul escapes an assassination attempt by a Harkonnen spy hidden inside the fortress walls. After the incident, Leto has Thufir Hawat place his soldiers on high alert.

In a visit to the stormy world of Salus Secundus, the Baron's mentat, Piter de Vries (David Dastmalchian), meets with an officer of the Sardaukar, fearsome warriors with a reputation for brutal and merciless combat. Piter makes a deal for three battalions to aide in their attempt at conquest of House Atreides on Arrakis.

Leto negotiates with the Fremen's chieftain Stilgar (Javier Bardem) and meets planetologist and imperial judge Dr. Liet-Kynes (Sharon Duncan-Brewster). Kynes is in charge of getting the spice harvesting back on track and has been appointed by the Imperial council to help Atreides. Kynes informs Leto, Paul, and Halleck of the dangers of spice harvesting, including giant sand-worms which travel under the desert. During a flight, they spot a sand-worm approaching an active spice harvester. When a carryall craft arrives to lift the harvester off the surface, one of its claws fails, making the retrieval impossible. Leto and his team rescue the workers moments before the sand-worm swallows it. In a rush of spice-laden desert air and sand, Paul is first exposed to the spice's narcotic effects, triggering intense premonitions. Back in Arakeen, Leto knows that if he cant get spice production back on track, it will lead to war. Kynes tells him that it was merely the failure of old equipment but that he should increase his protection of his family. When Paul comes home he is examined by Dr. Yueh, who says that he hasn't suffered any physical injury. Paul tells Jessica that he knows she is pregnant.

That night, Yueh disables Arrakeen's shields and allows Harkonnen and Sardaukar troops to overwhelm the Atreides forces. Yueh incapacitates Leto and tells him he made a deal to deliver him to the Baron in exchange for freeing his captive wife. Yueh replaces one of Leto's teeth with a poison gas capsule and is killed by the Baron after delivering the Duke. Leto releases the poison gas, killing himself and members of the Baron's court, but the Baron survives. Among the dead is the Baron's own mentat, Piter de Vries.

Duncan escapes and steals an ornithopter. Harkonnens capture Paul and Jessica and take them into the desert to die. Paul and Jessica overpower and kill their captors using a Bene Gesserit skill known as "the Voice", a means of controlling others verbally. Finding a survival kit left for them by Yueh, Paul and Jessica spend the night in a stilltent. Paul experiences visions of a "holy war" spreading across the universe in his name and is horrified at the thought.

The Baron gives command of Arrakis back to his brutish nephew Rabban (Dave Bautista) and orders him to sell spice reserves and restart production to recover the cost of the coup. Paul and Jessica are found by Duncan and Kynes and head to an old research station but are quickly tracked by Sardaukar. Duncan and various Fremen sacrifice themselves to allow Jessica, Paul, and Kynes to escape the facility. Kynes separates and calls a sand-worm to ride, but she is ambushed by Sardaukar troops. They tell her she has broken her loyalty to the Emperor. She retorts that she only worships "shai-hulud" (the Fremen name for sandworms) and the worm devours them all.

Paul and Jessica reach the deep desert in an ornithopter. It is whisked up by a massive sandstorm. Paul has a vision of another Fremen named Jamis, who tells him that survival in the deep desert is merely a process and he needs to flow with it. Paul shuts down the ornithopter's controls, folds up its wings and lets the storm carrying them to a safe level. They crash land and don a pair of stillsuits, uniforms that catch the body's moisture and allow survival in the deep desert. They try to cross the sand to a rocky location to avoid sandworms but when Paul steps on a patch of drumsand and it echoes, it attracts a worm. They run to the rocks for shelter but the worm stops short, seemingly "looking" at Paul until it is lured away by a thumper device. Paul and Jessica are found by a group of Fremen, who threaten to kill them. Jessica tries to negotiate a way off Arrakis but Stilgar deems her told old to learn their ways and says that Paul can. Stilgar attacks Jessica but she bursts into her Bene Gesserit defenses and takes the him hostage, while Paul runs to find a safer position, incapacitating Jamis (Babs Olusanmokun) on the way. Paul is found by Chani (Zendaya), the girl in his visions. Stilgar, realizing that Jessica is skilled enough to survive, orders his unit to stand down and declares that Paul and Jessica can be admitted to their clan. Jamis, offended that Paul overpowered him, protests their admission and is killed by Paul in a ritual duel to the death. Against Jessica's wishes, Paul insists on joining the Fremen to fulfill his father's goal of bringing peace to Arrakis. As they march with Stilgar's crew further into the desert, Paul spots a sandworm with a Fremen riding it. He realizes what his father meant by "desert power" and an alliance with the natives of the planet. Chani tells Paul "This is only the beginning."