Having your voice recorded for an animated film is a funny thing. You're standing in an isolation booth, generally with no more than one or two members of the production staff on hand. Chances are you've got cameras arrayed around you, especially if it's a CG-animated production. And script changes come fast and furious, as once the crew commits to a certain telling of the story, that's how it's going to be animated. There's no room for changes when even just getting a character's lips to sync up right can be a months-long process.

That's what Emily Mortimer went through during the production of Cars 2, Pixar's June 24 sequel in which she plays Holley Shiftwell, a smooth, "slightly over-enthusiastic" British spy-car. She spoke a little about her experiences in an interview with Spinoff Online earlier this week when she appeared for Disney's Cars 2 Toy Fair presentation in New York City. Questions about the film's story, even her own character's role in it, were met with confusion and hesitation.

"It only dawns on you towards the end of the process what your role is because it's such an organic process," she explained. "You say yes to the job without even reading the script. And then you get to read something of it but not really in a way that makes it clear what the story is, because at that point they don't really probably know themselves."

"So you lay down a whole load of dialogue in the first session, which goes on for many hours," she continued. "They're videoing you at the same time that they're recording you -- I think they use that in the animation [to carry across] some sense of your physicality, so that you really start to become this character. And then they take that away with them and they start devising the storyline as they go along and working out the role your car is going to play."

Mortimer said that over the course of the production -- it was little more than a year for her, a quick turnaround for this sort of animated feature -- she came in maybe seven times to record, and the content was always new, extensions from or changes to the original script. "The scenes, they change all the time. It's not like every time you do the session you re-read the script again," she said. "So it's sort of hard to see what's going on around you. There's this film being constructed around your ears but you don't really have an overall feeling about it."

She is sure that all of her scenes are with Mater, voiced by Larry the Cable Guy. The lovable tow truck has an expanded role in the sequel; no longer is he simply Lightning McQueen's sidekick. While the race car competes in the World Grand Prix, Mater ends up being mistaken for an undercover spy-type by Shiftwell and her boss, Finn McMissile (voiced by Michael Caine). An espionage plot plays out alongside the Grand Prix story, but Mortimer couldn't hazard a guess as to how much of the film will be spent on playing each one out.

Despite the difficulties in wrapping one's head around the larger story, Mortimer appreciated the freedom afforded to her by her voice recording sessions. "It's a very odd experience but it's very liberating in some ways as an actor, getting a chance to do work like this," she said. "At first you feel kind of self-conscious because you have to really go for it. You can't be shy, you just have to kind of be big and hope for the best. But it's cool because it forces you to sort of commit in a way to something, anything, just something really strong and definite."

"And you can experiment. There are no other actors there. There's only [director] John [Lasseter] and he's just so psyched about everything and such an enthusiast. You can really try things out that you wouldn't otherwise necessarily have the confidence to do, or the time or the luxury to do, on a film set where lots of people are waiting for the scene to be shot. Whereas this, you can do anything. And the more you become aware of that, the better it is as it goes along, and the more liberated you get about trying anything and seeing where it takes you."

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