How is this different from doing a live action movie? It's as if you're just doing a radio play. Occasionally there'd be a drawing, or the director would describe the scene, or they would have a rough video tape of something - very rough, usually stick figures. You had to use your imagination in the best of ways to get into their heads, because the animators sort of know what it's gonna be, but you help create their paints for them. I love this process, though it was frustrating sometimes because we did the opening of the movie, like, ten different times. I'd do it and then, a month later, come back and they'd go, "We have a new opening." "Didn't we do this?" "Yeah, but we don't like it, we tried it, it doesn't quite work." It's different than in a movie where you shoot it and then you know you have it or you do a reshoot.

There's a lot of you in your character, Mike... It's amazing, I mean, forgetting my little guy, John Goodman's performance is so stunning. He's a tremendous actor, and we did everything together, which I insisted on, because I just felt lonely the first two days, going, "This is silly."

So you got a chance to act together in the vocal recordings? Yeah, I said to the director, "I'm so lost here. I mean, I can riff all you want, but I have no one to play off, and these two guys have to be almost like a 30s comedy team."

Do you get the sense that your character looks like you? Yeah, oh yeah, but they videotape you while you're doing it. So there's usually two or three cameras on you, and there's also a guy who sits on a couch and just watches you and sometimes he has a video camera. And I'm very animated when I do it anyway, so my hands would move and so on, so the character moves like me. It was really spooky. When John Lasseter sent this script to me, they had taken some lines from movies that I had been in, and had Mike speak them. So I got a cassette, which was only about 45 seconds long, of Mike walking around talking about some stuff, but it was me. And I went, "Oh, good, but I don't think he should sound like me." I said he should be like Burgess Meredith in "Rocky", he should be Jiminy Cricket, but after a lot of coffee.

Did you ad-lib any risque adult humour? I did, but they didn't use any of it. I kept pushing, saying make that a little edgier, you can go a little further. But they know what they are doing.

What advice would you give another actor if they were asked to do the next one? Go with it, have fun, and bring your imagination with you.