While fans were left to mourn the unexpected death of Carrie Fisher in late 2016, her ongoing participation in the upcoming “Star Wars” movie will be ensured by using digital trickery and unused footage she filmed for “The Force Awakens”.

While seeing General Leia Organa one final time is bound to be a bittersweet experience for viewers, star Oscar Isaac admits the same held true for he and his co-stars.

Discussing the still-untitled “Star Wars: Episode IX” with The Daily Beast, Isaac says that the loss of Fisher and her character will be a big part of the film.

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“The story deals with that quite a bit,” he says of Leia’s exit. “It’s a strange thing to be on the set and to be speaking of Leia and having Carrie not be around. There’s definitely some pain in that.”

Shooting the new movie with J.J. Abrams (who directed “The Force Awakens”), says Isaac, has been a different experience than filming the first two, with the actor admitting “there’s a looseness and an energy to the way that we’re shooting this that feels very different.”

He adds: “It’s been really fun being back with J.J., with all of us working in a really close way. I just feel like there’s an element of almost senioritis, you know?” he says with a laugh. “Since everything just feels way looser and people aren’t taking it quite as seriously, but still just having a lot of fun. I think that that energy is gonna translate to a really great movie.”

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However, he lets fans know that the film will say goodbye to Fisher’s character in a way that honours her memory. “It deals with the amazing character that Carrie created in a really beautiful way,” he says.

“Star Wars: Episode IX” is scheduled to debut on Dec. 19, 2019.