Denis Villeneuve's 2021 "Dune" was absolutely stacked with A-listers, and the film scored two major stars to play Bene Gesserit witches, with Rebecca Ferguson as Lady Jessica and Charlotte Rampling as Reverend Mother Gaius Helen Mohiam. Needless to say, the TV show will be similarly stacked when it comes to casting their ancestors.

Two of the leading characters in the series are Valya Harkonnen and Tula Harkonnen, powerful women inside the Sisterhood — the organization that will one day become the Bene Gesserit. Emily Watson has been cast as Valya, and you'll most likely recognize the actress from her Emmy-nominated turn in "Chernobyl." And at one point, Shirley Henderson (Moaning Myrtle of "Harry Potter" fame) had been cast as Tula Harkonnen, but the actress stepped away from the project in February 2023 after a series of creative shake-ups. She's since been replaced by Olivia Williams, who's known for projects like "Rushmore," "The Sixth Sense," and "The Crown."

So who will be in the rest of the cast? Well, originally, Indira Varma of "Game of Thrones" and "Obi-Wan Kenobi" was meant to play Empress Natalya, but thanks to a reported scheduling conflict, she's been replaced by Jodhi May of "The Witcher" and "The Last of the Mohicans." May will be joined by the likes of Sarah-Sofie Boussnina, Shalom Brune-Franklin, Faoileann Cunningham, Aoife Hinds, Jade Anouka, Chris Mason, Josh Heuston, Edward Davis, and Chloe Lea. Plus, Travis Fimmel of "Vikings" will play Desmond Hart, a charming soldier who's working against the Sisterhood, and Mark Strong of "Kingsman" and "Shazam!" fame will play Emperor Javicco Corrino.