The most surprising moment in the first trailer for Star Wars: The Rise of Skywalker came in its final moments, when the evil laughter of Emperor Palpatine could be heard before the film's official title was finally revealed.

With plot details still hard to come by, a new rumor claims Emperor Palpatine's role is closely tied to an actor who has yet to be confirmed for The Rise of Skywalker: Matt Smith.

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A source for MakingStarWars.net reports Smith does appear in the film, and instead of playing the reincarnated Palpatine, Smith's character becomes possessed with the Emperor's spirit.

The possession then leads to an intense Jedi battle in The Rise of Skywalker's final act, with Rey and Kylo Ren teaming up against Smith/Palpatine. At some point Kylo kills Smith, forcing Palpatine to find a new host in the Knights of Ren leader. Kylo then begins to struggle while begging for Rey to kill him.

While the site says Kylo eventually becomes Ben Solo again before sacrificing himself, it's not clear if Rey is the one who kills Kylo, or if he does the deed himself.

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Of course, this rumor should be taken with a huge grain of salt. MakingStarWars.net even says it can't 100% confirm its true, as their source heard it internally. Also, when the site tried to press for additional details, it ran into numerous dead ends, which makes sense when you consider Smith's role is still in doubt. "As far as I can tell, I’m definitely not [in it]," Smith claimed in a March interview with the Los Angeles Times.

As we march closer to the release of The Rise of Skywalker, we should hopefully learn even more about the heavily-guarded ending to the Skywalker saga.

Directed and co-written by J.J. Abrams, Star Wars: The Rise of Skywalker stars Daisy Ridley, Adam Driver, John Boyega, Oscar Isaac, Lupita Nyong’o, Domhnall Gleeson, Kelly Marie Tran, Joonas Suotamo, Billie Lourd, Keri Russell, Matt Smith, Anthony Daniels, Mark Hamill, Billy Dee Williams and Carrie Fisher, with Naomi Ackie and Richard E. Grant. The film arrives Dec. 20.