For nearly half a century, the Star Wars saga has captured the hearts and minds of audiences. Now, with The Rise of Skywalker, the ninth episode in the Skywalker Saga, heading to theaters, the time has come to close the book on Star Wars as most people know it. But how do you say goodbye to something that will never end?

Chris Terrio, who in 2013 took home an Academy Award for his script for Argo, then went on to help craft Zack Snyder’s vision for Justice League, was hand-selected by J.J. Abrams to work on the final chapter. The task was wondrous but daunting: The Rise of Skywalker had to deliver a story greater than any individual’s imagination, while also leaving room for the galaxy to continue on in some capacity. A new set of Star Wars films is set to begin in 2022.

Sitting down with Polygon, Terrio explains where he and Abrams began in scripting Episode IX, where their creative journey took them, and ultimately, the personal lesson that he had to learn to do this final chapter justice.

Polygon: When you came into this project, Jurassic World director Colin Trevorrow already had a script, and he retains his “story by” credit. What was already in place?

Chris Terrio: Well, you know, J.J. and I are both a little superstitious about starting with material that we didn’t originate, just because it sends you down a road that maybe you wouldn’t have gone down.

So we actually started with just a whiteboard. At Bad Robot, there are these big rooms with just white dry erase boards. They literally just surround you everywhere. It’s very dramatic. The wall opens and the boards come out. So we started just with that. Literally, just writing and asking, “What do we want to see happen? These characters, where do we want to see them go? What are the feelings that we want to have? What are the stories that we want to tell? What things do we feel were unresolved either from VII or from VIII or even from Episodes I, II, III, IV, V, VI?” We kind of started with that and then, gradually, that dry erase board became a document that we just called “The Boards.” It was just a Word document that had all these ideas, which eventually grew to be, like, 121 pages of things that we would like to see.

Gradually, Darwinism takes over, and you cross out the things that aren’t quite making it. We started just from our own hearts and brains about where we wanted it to go, which is, you know, a great thing for a franchise of this size, because it didn’t feel corporate at all. We were just in Bad Robot, in a room. Just me and J.J., Michelle [Rejwan, Lucasfilm’s vice president of live-action production], and our other producer and Kathy Kennedy, of course. It was this process of iterating and then working with the designers, Rick Carter and Kevin Jenkins, who are both geniuses.

Rick, I’m sure you know his work, but Kevin hadn’t had a production designer credit before this film. He had been involved in concept work and art direction, and all kinds of position on Star Wars. He just knew everything about Star Wars, and his whole life he had been sketching Ralph McQuarrie drawings. I mean, from the time that he was a kid. So I’d have Rick — who’s, like, you know, this mystic — talking, talking about deep dives into the subconscious. Then Kevin is drawing, and then J.J., Michelle, and me and Kathy are all in the room. Then you add to that Roger [Guyett] at [Industrial Light & Magic], who is also a genius. I still have no how they did anything in this movie. So it became this little creative sandbox where we really could try anything.

The thing about a movie of this size is that you can imagine anything. Anything you can imagine, literally, can be realized in some way. It’s the only time in my life that I will ever have an experience like this. Not only that, but your heart is just brimming over because it’s Star Wars and it’s these characters that you love. They’re like your relatives. You love them. I feel that I know and love Luke and Lando better than I know some of my family, and I treat them with as much love and warmth as I would treat family. Or even more. So to have that at the warm emotional core of things, plus to have the ability to stage anything — any battle, that is, any event that is galaxy history — on a canvas that size, it’s a one-chance-in-a-lifetime thrill.

You’ve also written DC superheroes and talked about tapping into archetypes. Is that clash between good and evil the same archetypes as in Star Wars?

I’ve just been rereading some of [George Lucas’] early writings about Star Wars, even from 1974, and I think it’s a slightly different archetype set because — with superhero movies that are set on Earth, anyway — I found myself bound by certain realities of the interaction between the mythic world and the human world. Whereas, in Star Wars, you can have this Manichean fight between good and evil. You can even use terms like “dark” and “light” without irony, right? You can have a certain mythological earnestness that George put into the first movie, and that has only deepened and progressed since then. I found it to be very different. In fact, I found it to be much closer to the mythic heart of an epic. That, plus the experience of just writing characters that we’ve all grown up with, was mind-blowing.

Is that ever a hindrance, the fact that these people are loved ones?

Of course. I have certain scripts that I’ve written about people I know, or that are about my family, and they sit on the floor because, weirdly, it’s like, I don’t even want to mess with that psychic reality. Here, you have characters where you’re almost afraid, because they’re sanctified. Rick Carter said something at one point when J.J. and I were agonizing over something that happened in the third act. Rick said, “The reason you two can’t finish this is because you don’t want Star Wars to be over.” I sort of left the room and thought, “Rick is exactly right.”

J.J. and I were going in circles around this scene that should have been a pretty easy scene to write, but we actually didn’t want Star Wars to be over. We can’t do that because we didn’t want to. Because once we finished the outline of this event and the third act, it was over. That was it. I still don’t want it to be over. We were in the editing room just a few weeks ago, and you kind of want to memorize the room and memorize the emotion of it, because you know that you’re never going to get to be in that situation again. Even on set, I found myself just memorizing the place, because I just didn’t want to end.

That being said, Star Wars will continue. How does that affect creating finality?

Well, the ending of a story depends on where you stop telling it, right? I mean, the ending of war in Europe at the end of the First World War was a certain ending and seemed victorious. Then, that war in certain ways continued into the Second World War, right? And so we have stopped telling the story at the place where we think that the Skywalker Saga has finished its arc. There are other directions in the galaxy that are super exciting. I have been really excited by The Mandalorian. I love what Dave [Filoni] and those guys are doing. And women, too — I’m sorry, I shouldn’t say “guys.” I’m excited by whatever the next trilogies will be, but I did feel with this that we should spend our last two hours and something with these people that we’ve grown to know and love. I do think it’s really emotional. and I hope that it’s a fitting end that also feels inevitable.

You mentioned identifying loose ends from throughout the saga. How daunting does it become getting everything into a single movie?

I think that, by my last count, there were 24 character arcs in the movie. Twenty-four characters whose stories had sort of beginning, middle, and end. So it’s daunting, but also, we would tell ourselves that this is just the history of the galaxy. It’s not like we’ve got to make up some confection in order to fit in certain things. We said, “No, this is what happened. This is the battle that happened. This was the chance that they took. This was the plan.”

We would almost write it the way that I would write nonfiction. A lot of my past work was, like, historical drama and stuff like that. You write it in the way that you would write any world historical event or galaxy historical event, which is to say that there are all these interwoven strands and all these little moving pieces. But they all contribute to the end goal. It was daunting, but we could have written — I mean, it would have killed us — but we could have written three more movies. When we were in the room, we just wanted it to keep going. We wanted to keep exploring where things go. And yet, with this film, we also wanted to keep reminding ourselves that one of the things George said on [A New Hope] very early on was that the characters have to constantly be imperiled and constantly have to keep moving. The characters have to keep moving. You separate the characters, bring them together, separate them, bring them together, and you keep going, keep going, keep going. So that was our other directive to ourselves, which is just to keep the story moving.

I think there are also little parts of the galaxy that will be opened — at least to the imagination, if not to further films. We have some new characters in this movie that I would live with happily in my brain and imagination. So I hope that we’re also saying that the galaxy is big and various. We’ve shown you this one saga, but the galaxy contains multitudes. I hope it feels expansive and not like it’s closing anything off, although it is. It is doing both things.

I heard a proverb somewhere that says that “at the end of the thing lies its meaning.” I kept meditating on that and thinking, “How do we end this in a way that seems to sum up what’s come before?” We weren’t easy on ourselves. We really tried to ask, “What is this movie saying? What is this trilogy saying? What will all nine [films] be saying? Is it in the best spirit of George’s original intention?”

You mentioned identifying specific story threads throughout the saga. Can you elaborate a bit on that specific process?

We went back and asked, “What about this strand? Was this little promise that was made in this episode ever fulfilled?” Or, “Here’s a little aspect of this character that seems kind of interesting and intriguing,” or, as J.J. would say, “There’s always been this line in Empire Strikes Back, and I always think about that line. What do you think that means?” We could sort of play in that world for hours and hours and hours and debate and argue and grizzly-wrestle about certain points.

But, at the end of the day, we always came back to just our love for the characters. You love the story because you can’t really make Star Wars just with your head. There have been movies in my past that were sort of made more with head than heart, but with Star Wars you can’t. It’s bigger than any of us. You can’t think, Oh, I’m a grand genius of this saga, because you’re not. It’s not only George but the entire culture that has, like a glacier, collected around Star Wars. You can’t just check off this box or intellectually satisfy this. It really has to feel operatic. I mean, “space opera” is often used as a pejorative, but I actually love that term because I feel that the thing about opera is that you can’t contain the emotion with just words. It transcends, and that’s the thing about Star Wars, too. It’s bigger than us.

These two twins that are caught in this tide of history, and their mother who died, and how they were separated and their father turned to the dark, and then, eventually, redemption was possible — that’s really human and really moving and something that is so emotional. I get choked up even talking about it, like a crazy person, but we lived in the world for so long and we cared about it so much that you can’t just talk about it with your head. You have to like talk about it with your heart, and try to feel the stakes of it and feel the human drama of it.

I did want to ask: There has been so much talk about the “Snyder cut” of Justice League. I’m curious as to your thoughts on it.

And I have them! I do have them, but I won’t talk about it right now. We’ll have a date in a couple of months, and we’ll talk about it then. Because, you know, that is a really interesting topic that I have not spoken about yet.