Warning: Contains SPOILERS for Dune: Part Two and Dune Messiah!
Dune 3 is on the way, and while its recent casting announcement is exciting, it also raises a major question about Denis Villeneuve’s upcoming Dune adaptation. After the successes of Dune and Dune: Part Two, Villeneuve announced that he would be returning to direct an adaptation of Dune Messiah, Frank Herbert’s 1969 second entry into the book series. Although there are more Dune books after this, Dune 3 is set to be Villeneuve’s final entry in his trilogy, meaning that if there are any further Dune adaptations in this series, the director won’t be involved.
Denis Villeneuve’s Dune Messiah adaptation will pick up after the start of Paul Atreides’ Holy War from the end of Dune: Part Two, with the book taking place 12 years after Paul has become the Emperor. Although Paul’s theocratic regime causes all kinds of destruction across the galaxy, his visions make him realize that this is the best outcome for humanity. However, Paul’s genocidal actions have caused the Bene Gesserit and several other organizations to plot to overthrow him. The story follows Paul’s attempts to hold onto power as his control of the galaxy spirals out of control.
Paul Atreides & Chani’s Kids Are Only Babies In Dune Messiah, But Dune 3 Has Cast Young Adults
Both Actors Are Teenagers Already
One of the biggest developments in Dune Messiah is that Paul Atreides and Chani have two kids: a son named Leto II and a daughter named Ghanima. The two children aren’t born until well into the story of Dune Messiah, with Paul’s refusal to have children with Princess Irulan being a major storyline. Dune 3 has cast both of Paul and Chani’s children already. Nakoa-Wolf Momoa will play Leto II, while Ida Brooke will play Ghanima.
While these are still young actors, they aren’t as young as many Dune fans were expecting. Nakoa-Wolf Momoa is sixteen years old, and while Ida Brooke’s age isn’t known, she looks to not be much younger. This is surprising due to the fact that these children are only just born in the story of Dune Messiah. They should be babies in Dune 3, so casting much older actors is incredibly surprising. Although this change isn’t necessicarily a bad thing, it does set up a major departure for Denis Villeneuve’s take on the Dune Messiah story.
Is Dune 3 Also Adapting Children Of Dune?
There Is Precedent Based On Previous Adaptations
One possibile explanation is that Dune 3 could be adapting Children of Dune as well. Children of Dune is Frank Herbert’s third Dune novel, with it taking place several years after Dune Messiah. Leto II and Ghanima are the main characters of Children of Dune, and since Dune 3 is supposed to be Villeneuve’s last Dune movie, it makes sense for him to lift some elements from this book. Dune Messiah and Children of Dune have already been combined in the Sci-Fi channel’s 2003 adaptation Frank Herbert’s Children of Dune, so there is some precedent for these stories being packaged together.
How Dune 3 Can Make Sense Of The Atreides Twins Being Older Without Adapting Children Of Dune
There are already several theories that offer possible explanations for why Paul and Chani’s kids are older in Dune 3, outside of adapting Children of Dune. It could be that Dune 3 ends with a leap into the future, briefly showing older versions of Leto II and Ghanima. While it would be odd to announce their casting ahead of time since this would be a small appearance, it could end up being the case.

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Dune: Part Three – Confirmation, Cast & Everything We Know
After the explosive ending of Dune 2, Dune 3 could cap off Denis Villeneuve’s Dune trilogy by focusing on the events of the novel Dune: Messiah.
The other major theory is that Paul could have a vision of the older versions of his kids. His prescience has done something similar before, with Paul seeing an older version of his sister Alia, played by Anya Taylor-Joy, in Dune: Part Two. So, there are several ways that the ages of these actors could make sense in Dune 3 without the movie adapting parts of the third book.