Chris Pine and Isla Fisher may be much sought-after leading lights in their fields, namely action hero and comedic heroine respectively, but both admit to being intimidated by the skills needed for the animation adventure 'Rise of The Guardians'.
Fisher, star of 'Definitely, Maybe' and 'The Wedding Crashers', is so used to turning on an accent on demand, she tells HuffPostUK she felt "strangely naked" when director Peter Ramsey asked her to use her own voice for the role of The Tooth Fairy.
"I felt so self-conscious, I thought I had nowhere to go without the usual box of tricks," she remembers. "I just had to surrender to the whole process, and we got there."
Turning up just in time for the Christmas holidays, 'Rise of the Guardians' tells the story of a group of heroes - each with extraordinary abilities. When an evil spirit known as Pitch (the voice of Jude Law) lays downs the gauntlet to take over the work, the Immortal Guardians must join forces for the first time to protect the hopes, beliefs and imagination of children all over the world.
And, even though her fellow Aussie Hugh Jackman was on duty too, as the voice of the Easter Bunny, Fisher explains there was no chance to catch up on news back Down Under: "You're completely isolated as a voice artist. I had no idea what the film would look like until I sat down months and months later, and I thought, 'Wow, that's what you were up to.'"
Chris Pine, who plays Jack Frost in the film, agrees the whole exercise stretched a unfamiliar set of muscles. "I'm so used to playing physical roles, this was very novel. Hearing your own voice and working out what you can do with it."
The 32-year-old actor, at the helm of not one but two blockbuster franchises, playing Kirk in the 'Star Trek' reboot and picking up the baton of Jack Ryan (yes, the same Tom Clancy hero played by his Guardians co-star Alec Baldwin as well as Harrison Ford and Ben Affleck) in the forthcoming thriller of the same name, agrees all that could be equally challenging for a young actor, but he's worked out how to relax.
"I just surround myself with huge numbers of talented people, who know what they're doing. So there's no way I'm really carrying all that on my shoulders, whatever it may look like."
Rise of the Guardians is in UK cinemas today. Watch the trailer below...