With devilish glee and nasty cackles the Ugly Sisters are passing Cinderella’s invitation to the ball backwards and forwards in front of Cinderella’s nose. Each time the Sisters tear the invitation into even smaller pieces. However is Cinderella going to get to the ball?

Their father, Baron Hardup, decides to up his game, and bring his elder daughters under control.

“You need to be a bit sergeant major-ish,” suggests director Peter Duncan to actor Roy Weskin, playing the Baron. “No, don’t actually hit him,” he adds quickly to one of the Ugly Sisters as a fight breaks out between them.

It’s only the second day of rehearsals for this year’s Oxford Playhouse panto, but already a double act is building between Justin Brett and Miles Western, playing the Sisters, although they have never worked together before.

For Peter Duncan, however, it’s like coming home — this year’s Cinderella is the fifth panto running that he has directed for the Playhouse, and the whole saga of “Oh yes he is — oh no he isn’t” is truly built into his genes.

“My mum and dad were both involved in panto,” said Peter.

“My first memory is of being in the wings when I was very little, inhaling the smell of old costumes, seeing the coloured lights, and hearing the muffled sound of an audience not too far away. I do have an almost baby memory of it all.

“But my first conscious memories are of being a magician’s assistant in summer seasons, and being a stooge for my father.

“I would play the innocent — he would do a routine with a boy and a girl, you know: ‘Go on, put your arm round her, give her a kiss’, and I would dutifully do as he told me.”

At 15, Peter left the family nest, and launched himself on a career as a professional actor, and going on to become a presenter of TV’s Blue Peter. As a newly fledged actor, he came to the attention of the great Laurence Olivier himself.

“My parents were doing old-time music hall on the West Pier in Brighton — the one that’s now fallen into the sea,” Peter explained.

“Olivier and John Osborne were known to come and watch the show. I happened to audition for a play called The White Devil at the National Theatre, and became a tiny spear-carrier — although I was 16, I looked about 14.

“I was at the National for two years, it was like a training ground, working with all those good actors. At the time I thought it was all very different to panto, but now it feels closer together — panto is classic British theatre, and the National was just working in a different branch of British theatre: Shakespeare is close to panto in rhythms and language, although no one treats him like that.”

Back on the rehearsal floor, Peter moves on to a routine which involves a whole series of mops being caught by actors as they are thrown out from the wings.

One of the actors suggests dropping a line of dialogue to help him concentrate on the flying mops, and that begs an interesting question: besides directing the show, Peter Duncan has also written the script.

So if someone feels that some carefully crafted words should be cut, how does he react? Does he fly into a fury?

“I’m not really precious about it. The routine you were watching is an old routine, I can’t really claim to have written it. I’ve stolen bits, and added a few new things to it.

“The mop routine has been around for decades, the cast soon works into it, and it clicks.

“The skill is to add slightly new things each year, and pick songs from the modern genre as well.

“So many mistakes are made when people are precious about what they’ve written. If the writer is too strict, it can be a recipe for disaster.”

“I always think bad directors are the ones who start saying the actors’ lines out loud. I sometimes have to stop myself from doing that, telling the actors: ‘Say it like this’”.

lCinderella runs at the Oxford Playhouse from December 3 to January 16. Tickets from 01865 305305 or at oxfordplayhouse.com