'Rogue One' Sound Editors Reveal How They Found Princess Leia's 'Hope' and More Production Secrets

In many ways, Rogue One is unlike any previous Star Wars film — and yet, even in scenes featuring all-new characters, vehicles, and creatures, it feels like a Star Wars movie. Part of the credit for that goes to sound editors Matthew Wood and Christopher Scarabosio, who inherited the job of creating the Star Wars soundscape from original sound designer Ben Burtt.

Both Wood and Scarabosio have worked on every Star Wars film since Attack of the Clones, with Wood also supervising the sound in the Clone Wars and Rebels TV series, the Battlefront video game, and the DVD and Blu-ray versions of the original trilogy. Rogue One, however, offered some fresh challenges — including (spoiler alert!) the task of restoring a young Carrie Fisher’s voice to Princess Leia for the movie’s climactic final scene. As Wood explained to Yahoo Movies, Leia’s line was lifted from an alternate take of Fisher’s “help me, Obi-Wan Kenobi” speech in 1977’s A New Hope, found deep in the Lucasfilm archives. For more details on that and other secrets from Rogue One’s Oscar-nominated sound editors, read on.

Related: How the ‘Rogue One’ Ending Leads Us Right Into ‘Star Wars: Episode IV’ (Spoilers!)

What were your respective jobs on Rogue One?

Matt Wood: Chris and I were both supervising sound editors, but our tasks were split. So basically the easiest way to say it would be, Chris worked on sound effects, and I worked on dialogue. And we both have a huge knowledge of Star Wars lore. Ben Burtt [the sound designer on the original Star Wars films] has been a mentor to both of us.

Ben Burtt created all the iconic Star Wars sounds: Darth Vader’s breathing, the lightsaber whoosh, R2-D2’s beeps. How does your work connect to his?

Wood: Skywalker Sound, the sound division of Lucasfilm, was basically created around the work that Ben Burtt had done in the ’70s and ’80s. He’s still there, and he created a really vast library of Star Wars that is loved the world around. It’s our challenge to come up with new sounds to populate Star Wars, and then know when to play the old stuff and keep it connected. Like, you can drop in a Rogue One Blu-ray against Empire Strikes Back against The Force Awakens, and they’re all going to sound like they’re from the same universe.

What are your ground rules for making a film sound like it belongs in the Star Wars universe?

Chris Scarabosio: We both know the sound library so well that it’s kind of ingrained into our essence. There’s a certain aesthetic that we have working on these films, that you know when they’re right and when they’re wrong, and you just start trying stuff from there. Like certain sounds that I started with on some of the spaceships [in Rogue One], I thought initially that they were really new and original-sounding, but as [director] Gareth Edwards pointed out, they sounded a little too much like something that would be in a Tron movie and not something that would be in a Star Wars film. Which I totally agreed with.

It’s like you guys have an extra sense when it comes to the Star Wars universe; you notice things that are invisible to most viewers.

Wood: It certainly is that. John Gilroy, who’s the picture editor on the film, once looked at Chris and I, and he’s like, “You guys have a really great shorthand.” We both can make sounds with our mouths about what kind of thing we want — we’re looking for more of this, or that — and we just know the library really well to be able to pull stuff or create something new that’s going to work in a particular scene.

Did any sounds from the original Star Wars sound library make it into Rogue One?

Wood: Absolutely. For instance, that little mouse droid that Chewbacca screams at on the Death Star in the original New Hope. When K-2SO is retrieving the data out of the other Imperial droid so he can get a map of the station, you see a mouse droid go by. And that’s where we were like, “Well, we definitely have to play that original sound. We can’t make something new for that!” So those little details are something we try to put in as much as we can from the original. We have so much new material in there as well, so we’ve got to connect you back to it, and sound has that great ability to do that. It’s almost like music — how it can make you feel like you felt when you first [heard] it.

What would you describe as the signature sounds of this film?

Scarabosio: I’d say that the three ships — Krennic’s ship, Bodhi’s cargo ship, and the U-Wing — those ships all have what I feel are signature sounds. And then there are the weapons: Chirrut’s weapon, Baze’s weapon, all the rebel weapons. Then K-2, the new droid, and Bor Gullet, who was a new creature.

Watch a scene from Rogue One:

Carrie Fisher, who died suddenly last month, has obviously been on Star Wars fans’ minds. What was your role in creating the Princess Leia scene at the very end?

Wood: First off, we kind of knew what the script was going to be for that final line, how they wanted to put the button on the whole movie and then connect it right up to New Hope. So I got a call to try to find the original tapes of anything that Carrie had done from ’77. I found the original quarter-inch rolls in an archives box at Lucasfilm, and I just transferred every single take of the “Help me, Obi-Wan Kenobi, you’re my only hope” scene, the hologram scene from the original film. And there were a lot of takes. So I grabbed all that.

The machine that it was played back on doesn’t really exist that much anymore, so I was able to grab the special heads for that and transfer it into Pro Tools and just go through [the takes]. And John Gilroy and John Swartz, the producer, found a take that they thought really worked for that. So it is an original line from Carrie in 1977. [Producer and effects supervisor] John Knoll’s department had the main challenge of making that scene work visually, and I know that he mentioned that Carrie had seen almost the final project of what we had done there and actually liked it.

That’s so cool that you found all of the alternate takes!

Wood: It’s always fun listening to that stuff. Carrie Fisher used to always joke about those particular lines that were really tough to say, and I heard her original takes on those. She’d flub every fifth one or something, and it was funny because it really is a mouthful! And then she had to come back and do it again because there was another setup that I had found — they must have wanted to get two different angles, so they had to do it all again — and she was like, “I’m sorry!” when she would mess up. It was really cute.

K-2SO is a new droid who feels like he’s always been part of this universe. How did you approach the sound design for him, as opposed to other droids like C-3PO?

Scarabosio: Obviously I wanted it to sound different than C-3PO. K-2SO is a 7-foot-tall droid. So when I first heard about him, I thought he was going to be this big, really heavy droid — and he is — but there was something very elegant about the way he moved and the way he walked, and putting superheavy footsteps and big motor movements just didn’t feel right once we actually started seeing some renderings of him. So I tried to make his walk cycle rhythmic and not overly heavy on the footsteps.

For his motors, there were some motors I actually heard up in Vancouver the last time I was up there working. It was a front door in one of the places I was staying, this really big glass door. I really liked the motor, and so I had recorded it, but it wasn’t a great recording. It turns out that the type of motor it was is on handicap-assisted doors that open when you press a button. There’s one in the tech-building garage at Skywalker, and it’s that exact sound, so I went down there and just recorded the heck out of it, and then I started processing it to try and make it feel a little lighter. And that’s where we ended up.

Do you have a favorite Star Wars sound?

Scarabosio: The TIE fighter is one of my all-time favorite sounds.

Watch a video about how the characters in Rogue One were named: