OLD Mother Milly was Berwick Kaler's pantomime. It was his 21st York Theatre Royal panto, an entirely new show for the new Millennium built around the hardy annual dame. His role even gave last year's show its name.

What a contrast with this season's Dick Whittington, his 22nd panto in York. "It's not a dame's pantomime and it never will be," he says, explaining why Dick Whittington - up there with Cinderella in the pantomime popularity stakes - is being staged for only the third time during his damehood.

"It's absolutely basic with Dick Whittington that out of all the pantos, the kids tend to know the story better than any others. So you've got to open the story in London; you've got to have the store; you've got to have the ship and you must end up in Morocco - and basically I'm not good at sticking to that, am I?" he says, eyes imploring in that distinctive puppy way of his.

No, Berwick, you're not good at it! Last time, in 1991, he sent the ship to Scunthorpe, and artistically the show was his least satisfying of the past decade. "Yes, we haven't done it since you knocked it, have we?! But I do think this show's going to better than '91 - and don't forget that show had our best ever panto audience figures."

As ever, scriptwriter Berwick will not entirely be sticking to the plot, with the great York flood of 2000, the ailing railway network and a parody of BBC1 quiz show The Weakest Link all sure to feature. Names have been changed too, not to protect the innocent, you understand, but because that is the way of a Kaler pantomime.

Dick Whittington traditionally features Sarah the Cook as the dame's role, but in Kaler's world, Sarah makes way for Dame Cissy Sessay. Martin Barrass, the Dorian Gray of pantomime, takes on his eternally youthful sidekick status for a 15th year as the dame's son, this time playing Stanley Sessay, and Berwick makes use of the Pokemon craze by re-naming King Rat as Ratemon in the latest evil incarnation for David Leonard.

After the one-off, radical Old Mother Milly production, Berwick has decided to go to the other extreme this time. "Because last year was a futuristic show and a watershed pantomime - and I didn't have a single complaint about that - there's been a deliberate policy this year to make Dick Whittington as old-fashioned and child-orientated as possible."

That policy is all part of his drive to stay one step ahead. "What I have to do is protect myself from expectations. If you stay in one place for so long without changing the show, it would be the end of your panto 'reign'.

"I mean, how many ways can you throw a bucket of water? Believe me, we've thrown a bucket every which you can and yet people still want it to be different every year, and they're right to want that."

Now that Berwick is living in York - until last year London was his HQ - he predicts further changes afoot in future Theatre Royal pantomimes. "It does help me with ideas, going around and discovering places. Because I'm living here, I'm already excited about next year's show," he says.

Equally, he remains very proud of last year's millennium pantomime, indeed he seems hurt that more praise did not come the way of York Theatre Royal for putting on such a bold departure from the panto-norm. "No one in the national media gave us credit for doing a new show, but we were the only new show written especially for the millennium," he says. "At least the Guardian last week said we're the only pantomime in the country worth seeing.

"Mind you, that makes me nervous as I don't want the panto putting on a pedestal, because there's a nasty tendency in Britain to want to knock people off their pedestals."

In truth, he faces that risk every year, and yet the Theatre Royal pantomime continues to grow both in reputation and in length. This season the run will stretch into February for the first time, making even more physical demands on Berwick's 54-year-old frame.

What a good year for Berwick to have given up smoking. "I used to smoke at least 60 a day, possibly even 80, but this year I went on a very long journey in February to Hawaii and that holiday needed about 14 flights. I think I had to go 24 hours without a fag, and I wasn't an absolute nervous wreck; I wasn't screaming for a ciggie. So I decided to stop and haven't smoked since May."

Yet ironically his next television appearance, in Casualty on BBC1 in mid-January, casts him as a heavy-smoking, hospitalised university lecturer. "Even when he's in hospital, he's asking everyone for a fag," says Berwick.

Not so, Berwick Kaler. From now on, his motto is no smoke, but still plenty of fire.

Dick Whittington, York Theatre Royal, December 13 to February 3. Tickets: £8 to £16, with concessions available; ring 01904 623568.