The task of ending a saga as beloved as Star Wars is difficult for even the greatest writers. It's important to work with people who can be trusted with such a weighty task. Luckily, Star Wars: The Rise of the Skywalker had two dedicated fans crafting its story.

During a press in Los Angeles, director J.J. Abrams and his co-writer Chris Terrio spoke about the process of creating the story for the film, the pressure that came with it and what it was like to finish the Skywalker Saga.

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As anyone who found out they'd been hired to tackle Star Wars would be, Terrio was initially surprised and overwhelmed by the news. "You spend about eight minutes doing somersaults," he remembered. "I was in Manhattan when I got the call from J.J. Abrams. He'd been calling and leaving messages and I'd been in a screening. And I didn't have J.J.'s cellphone number, so it was this sort of random 310 number. I was wondering why this person in Los Angeles was calling me. Then I listened to the message and started hyperventilating.

"So I called back, and he asked if I wanted to write Episode IX with him. He didn't say 'Star' or 'Wars', just Episode IX. So, for a good eight minutes, I let myself leap into the air. And then I realized, oh my God, we have to land this vehicle. We have to land the largest Star Destroyer in the world on the head of a needle."

Terrio had to move across the country to work with Abrams for the duration of the process. "I live in New York but I flew out to Los Angeles. And J.J. and I -- at [Abrams' production company] Bad Robot there is this room with these big whiteboards -- and we started writing with dry-erase markers on blank boards. And then the blank boards were a Word document that was 10 pages long, then 50 pages long, then 121 pages long. And then that became the script."

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For Abrams, who also wrote the first film in the sequel trilogy Star Wars: The Force Awakens, it was crucial that he worked with someone like Terrio while crafting the final part of the Saga. Abrams explained, "I will only add that when I called Chris about doing this -- and you were such a big Star Wars fan, which I had been told -- I was such a fan of Chris' screenplays, and Argo I thought was so beautifully written. I needed to have someone writing this with me who from the very beginning reminded me of how much Star Wars meant who hadn't been in it in a way I had.

"I said at the very beginning," Abrams recalled, "'you're going to be with me this entire time, to the very end.' And Chris being the humble man he is, made a self-deprecating joke about me not wanting him around by the end. We were together [in the trenches], kicking every tire, shaking every tree to make the story as good as we could and I can't tell you how grateful I am for this gentleman's partnership."

No matter how exciting it was for the pair, it eventually had to come to an end. As they approached the conclusion of the script-writing process, Terrio admitted it got more difficult. "There was a moment in the process when J.J. and I were agonizing over something in the third act... and we just couldn't seem to get it. And we went out of the room and ran into Rick Carter, this legendary production designer, [who] said 'I think the reason you can't write this scene is that you don't want Star Wars to end.' And then I looked at J.J. and we knew he was right. So we went in and we finished it.

"The movie is, of course, remade in the edit and then with the scoring, so we kept rediscovering the story along the way.... We both mourned the moment where we typed the character's name for the last time.... It's memorable."

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, Anthony Daniels, Mark Hamill, Billy Dee Williams and Carrie Fisher, with Naomi Ackie and Richard E. Grant. The film arrives December 20.

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