Dune: Part Two, the second half of Denis Villeneuve’s two-part epic, adapts the latter part of Frank Herbert’s classic sci-fi novel, Dune. Translating the nearly 700-page book to the screen required Villeneuve to make some crucial changes. Not only was runtime a factor, but the director had to streamline certain plotlines and characters to make Dune and Dune 2 more digestible for movie-going audiences. That said, Dune 2‘s book changes are completely reasonable, especially considering the unique needs of the medium of film. Still, the alterations will have a massive impact on Dune 3.

Set to adapt Dune Messiah, Herbert’s first Dune sequel, Villeneuve’s Dune: Part Three will likely pick up years after Dune 2‘s ending, and chronicle how the newly minted Emperor Paul Atreides’ (Timothée Chalamet) role as the Fremen messiah unleashed a bloody holy war across the Known Universe. Paul’s stranglehold over spice production, and the billions killed in his name, push the Bene Gesserit sisterhood to team up with unlikely allies in order to dethrone Paul. While the plot seems straight-forward on the surface, Villeneuve’s Dune 2 will drastically change several key plots and characters in Dune 3.

Dune 3 Must Introduce The Spacing Guild

The Guild Plays A Crucial Role In Dune Messiah That Wasn’t Really Set Up In Previous Dune Movies

Without a doubt, Dune 2‘s biggest book omission creates a major problem for Dune 3‘s story. With so much to squeeze into his two-part sci-fi epic, Villeneuve decided to cut the Spacing Guild from his films. Crucial to the Known Universe’s political and economic structures, the Spacing Guild tries to thwart the Bene Gesserit’s Kwisatz Haderach plan and Paul’s rise to power in Herbert’s Dune after realizing that the Atreides heir poses a threat to the Guild’s monopoly on faster-than-light space travel, transport, and interstellar banking.

The Spacing Guild won’t have the same storied presence it does in the books.

Despite being an interstellar shipping and trade conglomerate, the Spacing Guild — also known as the Guild of Navigators — wields power equivalent to the Imperium and Dune‘s Great Houses and factions. The sequel sees the Guild aligning with the Bene Gesserit and Tleilaxu organizations in order to dethrone Paul. In particular, a Guild Navigator named Edric, who shields his prescience from Paul’s visions, plays a crucial role in Dune Messiah. While Dune 3 can still give the Spacing Guild a proper introduction, the group won’t have the same storied presence it does in the books.

Chani Won’t Be Paul’s Concubine In Dune 3

Dune 2’s Ending Sees Chani Leaving Paul Behind After He Accepts His Role As Messiah

At the end of Dune 2, Chani (Zendaya) abandons Paul. Although she loves him, Chani can’t stomach Paul’s decision to drink the Water of Life and become the prophesied Fremen messiah. In Herbert’s Dune, Chani is less critical of Paul’s actions, and stands by him as he claims the Emperor’s throne. Although Paul marries Princess Irulan (Florence Pugh) for political gain, Chani remains his “concubine,” and the two try to conceive children together. That said, Chani’s Dune 3 role will change drastically in light of Villeneuve’s choice to have the Fremen warrior walk away from Paul.

Princess Irulan’s Plot Will Change Without Chani

In Dune Messiah, Irulan Thwarts Chani’s Attempts To Become Pregnant

In Dune Messiah, Irulan remains an agent of the Bene Gesserit, working closely with Reverend Mother Gaius Helen Mohiam (Charlotte Rampling) to curb her husband’s influence. While Irulan is married to Paul, the couple don’t try to conceive an heir. In order to ensure Paul doesn’t have children with Chani, Irulan secretly gives contraceptives to Chani. Desperate to preserve the Bene Gesserit breeding program, and fortify her place in Paul’s empire, Irulan endangers Chani’s life. Although Paul is aware of Irulan’s plot, he doesn’t stop her; his prescient visions have hinted at Chani’s death during childbirth.

…it’s not clear how Villeneuve and his team will reconcile Paul and Chani’s crucial relationship.

All of that said, Irulan’s role in Dune 3 will change along with Chani’s. Since Chani leaves Paul at the end of Dune 2, it’s not clear how Villeneuve and his team will reconcile Paul and Chani’s crucial relationship. While Irulan is clearly going to remain a Bene Gesserit agent, her role in helping the order might change. Interestingly, Dune 2 retained Lady Margot Fenring’s subplot in which she seduces Feyd-Rautha Harkonnen, suggesting that the Bene Gesserit may have other plans for their carefully curated bloodline in Villeneuve’s version of the Dune universe.

Chani’s Dune Messiah Death Might Be Avoided

The Fremen Warrior’s Life Is Endangered By Her Pregnancy

In addition to changing — and effectively complicating — Paul and Chani’s relationship, Villeneuve’s Dune 2 cuts Paul and Chani’s first son from its narrative. To avoid runtime bloat and unnecessarily confusing story elements, the director wisely circumnavigates the sudden birth of Leto II, who is pretty abruptly killed as an infant during a Corrino raid. While Dune 3 could reveal that Chani gives birth to Paul’s child (or children) in the interim, it’s unclear how the third film will handle Paul and Chani’s fractured relationship.

Chani’s tragic death in Dune Messiah devastates Paul…

In Dune Messiah, Chani subverts Irulan’s tampering by starting on a Fremen fertility diet. However, since she was long-exposed to Irulan’s contraceptive measures, Chani is severely weakened, which endangers both her pregnancy and her life. Ultimately, Chani dies during childbirth, leaving Paul with twins — Leto and Ghanima — who have inherited his access to ancestral memories. Chani’s tragic death devastates Paul, pushing him toward his desert-wandering fate. Moreover, the loss of Chani means that the twins grow up with their aunt, Alia (Anya Taylor-Joy) and Irulan. Dune 3, however, has the chance to change Chani’s story.

Alia Atreides Must Be Properly Introduced In Dune 3

Alia’s Role Changed Significantly In Dune 2

Instead of properly introducing Alia Atreides — Paul’s younger sister who is born a full Reverend Mother — Dune 2 wisely teased the character’s future role in the franchise through Paul’s visions. Throughout Dune 2, Lady Jessica (Rebecca Ferguson) is also able to telepathically commune with her unborn child, adding a kind of looming menace to Alia’s character. Canonically speaking, Dune Messiah is set 12 years after the first book, but it’s hard to imagine Dune 3 sticking with a similar timeline. That, of course, poses a potential problem where Alia and Paul’s ages are concerned.

Apart from that age-gap issue — Taylor-Joy and Chalamet are similar ages, making a 12-year-gap a little tricky to navigate — Alia’s backstory will be quite different. In Herbert’s Dune, Alia kills Baron Harkonnen, while Villeneuve gives that honor to Paul. Given Alia’s future Baron-centered plotline in Children of Dune, the change poses some thematic issues and undercuts Alia’s out-of-the-gate ruthlessness. Alia, the regent for Paul’s twins, is central to Dune 3‘s story, which means Villeneuve will have to carefully consider her proper introduction into the franchise.