Billy Bob Thornton has admitted he found his first venture into voice work "intimidating".
The actor stars as Jack in the spin-off to the hit Shrek franchise, but at the film's Los Angeles premiere, he said he found the experience daunting.
"I was very nervous doing this because you're by yourself and you're not in the real environment, it's very different to what I'm used to doing," he explained.
"I was intimidated because I've never done one of those big animated films."
Luckily he managed to overcome his nerves - and hinted he might even be willing to return for a sequel.
He said: "I had a great time and I think next time I'll be more relaxed."
In the meantime, the Oscar-winner is focused on his next directorial project, 1960s drama Jayne Mansfield's Car.
"We're still in post-production. It felt good to be back in the director's chair again," he added.