One of the most surprising additions to Star Wars: The Rise of Skywalker is a posthumous appearance by Carrie Fisher, who's reprising her role as General Leia Organa years after her death.

For director and co-writer J.J. Abrams, Fisher's inclusion through footage of unused scenes from 2015's The Force Awakens helped the filmmaker crack the story for Episode IX.

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"It’s hard to even talk about it without sounding like I’m being some kind of cosmic spiritual goofball," Abrams said in an interview with Vanity Fair. "But it felt like we suddenly had found the impossible answer to the impossible question."

Re-lighting sequences to match the film quality and lighting from the 2015 film, Abrams integrated deleted scenes into the upcoming sequel. Originally, he had deliberately avoided writing scenes with Leia and Fisher's daughter Billie Lourd together due to the potential emotional strain on Lourd performing opposite her deceased mother, though Lourd convinced Abrams to write and film scenes between Leia and Lourd's character Resistance officer Connix.

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"There are moments where they’re talking; there are moments where they’re touching," Abrams explained. "There are moments in this movie where Carrie is there, and I really do feel there is an element of the uncanny, spiritual, you know, classic Carrie, that it would have happened this way, because somehow it worked. And I never thought it would.”

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 December 20.