In an interview with Vanity Fair , J.J. Abrams said he remembered there was still some unused footage of Fisher left over from the 2015 film "The Force Awakens" that could be incorporated into "Skywalker."

"It's hard to even talk about it without sounding like I'm being some kind of cosmic spiritual goofball," Abrams said, "but it felt like we suddenly had found the impossible answer to the impossible question."

Abrams began writing scenes around the old footage, so Leia's dialogue could fit into the movie in different ways.

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