WARNING: SPOILERS ahead for Dune: Prophecy episode 4.
Sister Theo Surprisingly Reveals Her Shapeshifting Ability Dune: Prophecy episode 4 “Twice Born”, which indicates that she could be a “Face Dancer” based on Dune tradition. Dune: Prophecy is a six-part series based on the 2012 novel Dune Brotherhoodwhich was written by the original Dune son of author Frank Herbert, Brian, and Kevin J. Anderson. The story takes place more than 10,000 years before the rise of Paul Atreidies, narrated in the book by Denis Villenueve. Dune (2020) and Dune: Part Two (2024). Dune: Prophecy reveals the origins of the powerful shadow brotherhood known as the Bene Gesserit and how they manipulated the destiny of humanity.
Dune: Prophecy Episode 1 “The Hidden Hand” introduced Emily Watson's Valya Harkonnen, a fierce and calculated leader, and her biological sister, Tula Harkonnen. Dune: Prophecy Episode 2 reveals what happened to Lila and her grandmother, Reverend Mother Dorotea, after Tula and Valya Harkoennen encouraged her to prematurely endure a life-threatening ritual known as The Agony. In Dune: Prophecy episode 3, Tula takes Lila's life into her own hands after she apparently died during the Agony ritual and attempts to resurrect her through the use of forbidden technology. Episode 4 reveals that Lila was resurrected through the Thinking Machine, Anirul, while Valya has her own secret weapon in Theo.
Theo reveals she is a shapeshifter in Dune: Prophecy Episode 4
Theo feels cursed with this shapeshifting ability which Valya sees as a gift
During the end of Dune: Prophecy episode 4, Sister Theo shockingly transforms into Valya's brother Griffin, revealing that she has superhuman shape-shifting abilities. Valya blames Vorian Atreides for the death of her brother Griffin, who she believes was murdered decades earlier by Vorain Atreides. At the beginning of episode 4, Valya makes reference to Theo's “gift”, which angers Theo deeplywho says he doesn't consider it a gift. This implies that Theo feels she is cursed with this shape-shifting ability, which Valya is clearly using to further the Brotherhood's control over the Empire and her underlying plan for revenge against House Atredies.
Theo has always been one of the Brotherhood's best students in the entire Dune: Prophecy but it was unclear why she was accompanying Valya to visit her uncle Evengy and nephew Harrow. Now that she is revealed to be a shapeshifter, it is almost certain that Valya will use Theo to further her agenda of restoring the value of House Harkonnen and reaffirming the Brotherhood's position throughout the Empire. Theo transforms into Valya's brother Griffin to help her deal with the eternal guilt of his death.which still deeply motivates his actions to this day.
Face Dancers in Dune Lore Explained
Frank Herbert initially introduced Face Dancers in Dune: Messiah
Based on the reveal of Theo's shapeshifting abilities It's possible she's a “Face Dancer” based on Dune tradition established in the book series. Original Dune creator Frank Herbert initially introduced the Face Dancers in Dune: Messiahwhich will be the basis of Denis Villeneuve's third and final film, Dune. According to Dune Wiki“Face Dancers were a sterile race of shapeshifting transhumans engineered by the Bene Tleilax..” The Bene Tleilax, or Tleilaxu, are “a group of secretive, genetically altered humans who inhabited Tleilax, the only planet of the star Thalim” (via Dune Wiki).
Similar to the Bene Gesserit's ambitions to create ideal rulers based on their genetic reproductive index, the Bene Tleilax are also highly sophisticated genetic engineers. One of the subspecies that Bene Tleilax spawned became known as Face Dancers, which is likely what Theo is. Interestingly, Theo seemed to be the most poisoned and knowledgeable of his fellow sisters, and now it's clear why. If Theo is a Face Dancer, she is able to transform into anyone and replicate their appearances and personalities. Theo herself may be based on someone else. Or maybe Valya killed the real Theo and replaced her with a face dancer.
How the Existence of Face Dancers Completely Changes Dune: Prophecy
Theo may not be the only shapeshifter in the series​​​​​
Despite its strangeness, Theo's shapeshifting appears to calm Valya after her uncle continues to blame her for Griffin's death. Theo also appears to have human qualities, which is said to be the result of a Face Dancer who became delusional about his identity after living as a person for a long time. Theo could have been a spy sent by the Bene Tleilax for the Brotherhood which Valya exposed since Mother Reverends can detect these shapeshifters easily based on Dune tradition. What is clear in Dune: Prophecy after four episodes is that Theo is a valuable tool that Valya will likely use to get closer to Keiran Atreides or Desmond Hart. It also begs the question: who else could be a Face Dancer?