Park: I feel like we're constantly drawing on all these different movie genres or experiences that we've had. We pretend not to go to movies and look at them for that purpose, but movies are in your subconscious. You know, it's a whole culture that we've been brought up on. And I think we are constantly switching, aren't we? I think that's the beauty of this medium: You can constantly switch from a live-action world where characters exist in space, where the world is gritty and characters have gravity, to suddenly be very cartoony. You can constantly set up expectations and break them. I enjoy playing with going from more cartoon traditions to going more toward Hitchcock and then to whatever. That's why it's a beautiful medium.

Lord: And to answer the other part of the question: When we work with actors, we still listen to the voices with much the same ear as for the documentary stuff. I think we tend to choose the most natural takes we can. "Natural" may seem to be a strange word for us to use, but we listen for very natural vocal performances. Just as in the documentaries, we're hoping to hear those gaps and hesitations -- the spaces between words which imply what's going on in the speaker's head. That kind of thing.

It's so difficult to alter a puppet in midproduction. Is it more challenging for puppet animators than computer or cel animators to come up with durable concepts for characters? For example, Jane Horrocks' character -- a chicken who acts like an ostrich, refusing to see evil and viewing the heroic Ginger's time in solitary as "a holiday." Did you have a pattern for that in your mind, or did it emerge partly from listening to Horrocks do those lines?

Lord: Actually, the underlying concept is sort of based on Jane's voice, isn't it? This funny thing about her being quite still. I mean, she's busy because her hands are busy and the face is just as animated, but she's very kind of square-on the whole time -- very square-on and bright, with madly bright eyes.

Ironically bright eyes -- otherwise, she's dim.

Lord: Yes, yes, indeed. An interesting detail is she's got this strange fringe of hair. She doesn't therefore as a result have a brow to play with, so it kind of changes her range of options. In fact, you could say she is the ultimate in limited palettes because her body is massively immobile -- I mean [pat, pat], like this sofa really. All she's got is this body that won't do very much and this head that works best straight on at you.

Park: And that's completely the opposite from what we're often saying, which is that we love clay because it's so flexible, malleable, and we can do all this fleshy, human kind of animation.

That was actually in the back of my mind: Was part of the attraction of chickens that they seem so inexpressive? Did you get drawn to that because it automatically became a challenge to your ingenuity?

Park: We didn't really even look at chickens for very long, because they were so awkward: They twitch all the time, they have eyes on the sides of their heads, they don't have any teeth, their legs bend the wrong way. They were completely the wrong thing to choose for our kind of animation.

But what I'm asking is, was that part of the attraction?

Lord: The fact that they were very awkward to animate wasn't part of the attraction. But the fact that they're so gormless [British slang for slow-witted] -- if I can say chickens are gormless -- was definitely part of the attraction.

So you saw the humor in their being so woebegone.

Lord: Yes, yes.

Park: I remember that we had a lot of discussion at one point as to how human and how chicken are the characters. I think we went quite far off into the human, but in a cartoon way. So they all became very unathletic, middle-aged women. And that's where a lot of the humor comes from. They have generally large shapes, but simple, quite simple, shapes. So they could stand there and have a deadpan look, but say a lot by not doing much. You know what I mean?

Of course. And that must've inspired the workout session, right?

Park: Yeah, the chickens were very restricted in what they could do, especially the bigger ones. So it looks funnier when they are trying to exercise or trying to run or whatever they're trying to do.

Talk about movies bubbling in the back of your mind -- anyone who loves "The Great Escape" can see so many resemblances in "Chicken Run." Some of the fun for you must have been saying, "Well, we'll have to do some kind of Steve McQueen motorcycle scene" or "We'll have to have someone toss a ball against the cooler wall."

Lord: Yes, that's exactly right. I reckon those ideas came up probably in the first hour -- and stayed with us over the next four years. They were always destined to be in there, those ones you mentioned, and Ginger [the chickens' leader] rolling through the underground tunnel on her belly on that truck trolley, which in her case is a roller skate. And that sort of thing where they have to cover up what they're doing -- they spin around secret panels, like what happens when Donald Pleasance's forgers turn themselves into a bird-drawing class. They devise cunning schemes to cover up what they're doing so the guards can't see. Yeah, we knew it would be there from the start.

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