The star recently opened up about what it was like to work with the famous brothers, and revealed two other celebs who made low-key cameos in the upcoming sci-fi epic.
The news of their regal cameos was revealed by star John Boyega during a recent taping of The Hollywood Reporter's Actors Roundtable, where he dished on their scene -- and a few other famous stars who also secretly donned Stormtroopers outfits.
Boyega -- who plays Finn in the Star Wars series -- confirmed reports that Mad Max: Fury Road star Tom Hardy and English singer Gary Barlow were also "wrapped in Stormtroopers costumes" during filming.
According to THR, the scene in question saw the princes, Hardy and Barlow all standing guard around Boyega's character.
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The actor said during the roundtable discussion that the four celebs all decked out in the iconic armor made for a "strange contrast of a weird family."
"It was a great experience," Boyega marveled at the "fun" opportunity to perform alongside members of one of the most powerful and influential families in the world.
Rumors of William and Harry's involvement on the film sprang up in April, when the brothers took a tour of Pinewood Studios in London, where parts of The Last Jedi were filmed. While there, the pair visited the production workshops and met the cast and crew of the latest installment in the blockbuster sci-fi franchise.
Boyega, Mark Hamill, Daisy Ridley and director Rian Johnson were on hand -- along with Chewbacca, BB-8, and producers Ram Bergman and Kathleen Kennedy -- to meet with the duo, and give them a tour of the set.
Harry got to sit in the cockpit of an A-wing fighter, while William got a chance to make friends with everyone's favorite rolling droid. And, obviously, both of them got hugs from Chewbacca.
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The star-studded cameos in The Last Jedi are similar to the largely unnoticed cameo Daniel Craig had in The Force Awakens, where he played a Stormtrooper who gets unwittingly manipulated by some Jedi mind tricks.
Fans can check out the very clandestine cameos when Star Wars: The Last Jedi hits theaters Dec. 15.