You have never seen Becky Sullivan in a movie. You haven’t even heard her voice. But you’ve certainly listened to her work as a lead sound and automated dialogue replacement (ADR) editor on dozens upon dozens of blockbusters in her 25-year career, including Field of Dreams, The Fugitive, Batman Forever and L.A. Confidential. She was Angelina Jolie’s first choice to work on her directorial debut, In the Land of Blood and Honey. She did all the superhero dialogue in the record-breaking Avengers. And she lent a hand in Ridley Scott’s Prometheus, in theaters Friday. Sound—or more often, lack of sound—has played an important role in the Alien franchise. Sullivan recently stepped off the G.I. Joe: Retaliation set in Hollywood long enough to chat with TIME about battling the elements, creating alien dialogue and the sound of silence.
What is the role of an ADR editor?
I listen to all the dialogue tracks, everything shot in production on the set and on location, and evaluate the sound to see if it is good or not. I specialize in action films—and in action films there is generator noise, wind machines, gunfire and helicopters. When you are live on a set, the microphone is on, picking up everything around the actor. Most of the time the voices marry to a helicopter noise or a blank gunshot, so then we have to replace it.
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How much do you change?
I go through the movie—all 2,000 lines—and write down every line of dialogue that needs to be replaced and give reasons why. I talk to the director about it and discuss sound problems and different ideas and see if they want to do performance changes. We have revoiced entire performances before. Sometimes I get a director’s thoughts and work with writers to get them to rewrite story points.
How do the rerecords work?
We get the actor in for looping and go onto an ADR stage specially made for what we do. There’s a recordist and a mixer in there and we record the line while we see the movie played back to us. The actor is watching himself and listening to the set through headphones. If he yells ‘hey guys’ at 14 feet [of film], then he does it on the ADR stage. We do take after take for every line to get the right performance, right tone, right volume and right timing. I digitally cut every word into their mouth to make sure it doesn’t look like talking Kung Fu.
How does sound work differ for each film genre?
The action genre is more challenging because you have a lot to do. I’m on G.I. Joe here [in Hollywood] and we’ve done a lot of looping due to the wind on set. When you are out shooting guns, the dialogue often gets ruined. I have done several comedies where the subtleness of a line hitting the right tone becomes important. I’ve also done comedies where they want to rewrite lines to make them funnier or add story points.
How big a role do you play?
The cool thing is I get to direct actors. Certain directors even let me on the set with the actors without them. I hit it off with the actors and it is really fun—that is my specialty. Some actors are really good at it and some love the loop because they know they can subtly change a performance, a word or a feeling. The better the actor is—the more high profile an actor—the better they are at coming in and doing magic. It is part of their craft. I can tell the new actors right away because they aren’t used to doing it.
Can you talk about working with Angelina Jolie?
She was fantastic. She was new to the post-production part of a movie, but was so willing to learn and understand the craft. We shot two films at the same time with two different languages. First we shot in English and then would switch and do it in Bosnian/Croatian/Serbian language. It was very challenging cutting dialogue and looping actors in that language.
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How do you deal with mixing together audio where some creatures don’t exist in the real world, like the aliens in Avengers?
Luckily, I am a fan of Marvel’s films, so I knew all the characters and each back story. Many times I will record actors to voice aliens or creatures. You get the organic human sound from the actor and then process the voice using different digital sound design techniques. You can design the voice a million different ways.
How close of an eye do you keep on other big-name films?
I am always going to see films, watching and listening to other people’s work. The sound community in Hollywood is very small; we all know each other and respect the creative talent that each person brings to a project. There is always more to hear and things to learn.
What was your role in Prometheus?
I cut the ADR breaths that each actor recorded on the ADR stage. Funny, right? But even the sound of the characters’ breaths is important to sell the story and put the filmgoer in the scene.