It's been 13 years since Wallace and Gromit's last short film. Was it easy to return to TV?

Having done two films back to back, this was very refreshing. I was more in control and able to do it in a shorter time. I got one note from the BBC on the whole film. When you work in Hollywood, you get endless reams of notes. You lose the sense of what you want.

Did you ever think the duo would be so durable?

I've been very lucky. When I was a child I used to watch The Clangers, Noggin the Nog, everything by Oliver Postgate; I used to think, wouldn't it be great just to be on the BBC with characters that are so well known. When I got my first job on Morph, it was like a dream come true.

Where did the names come from?

In an early version, Wallace was a postman called Jerry. Jerry and Gromit just doesn't have the same ring. But then I remembered this old lady on a bus in Preston. She got on with a fat labrador called Wallace, and it struck me as a funny name, a very northern name to give a dog. Then, my brother was training as an electrician and talking about grommets. For me, it's always the way a word feels or makes a mouth move.

Is A Matter of Loaf and Death the quickest film you've ever made?

It must be. The first Wallace and Gromit took seven years. This one took seven months, because I was able to use teams of animators.

Does that mean you compromise?

I hope not. I still want everything to work perfectly, from the positioning of cups on the table to the timing of the jokes. By the time the film is finished I lose track of whether the jokes still work, so sitting in a screening is still a terrifying experience.

How do you start the film-making process?

After we have got the script and the voices recorded, I do what we call a LAV test: Live Action Video. I perform all the roles of all the characters, so that the animators know what sort of facial expressions I want the characters to pull. I hope those videos never see the light of day!

You still have fingerprints in the characters' Plasticene, though...

We're very proud that it's hand-made, and we don't want to tidy things up too much. Those thumb prints are a reminder of the work that went into it.

Wallace & Gromit: A Matter of Loaf and Death, Christmas Day, BBC One, 8.30pm

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