At the Unicorn Theatre an ugly duckling may be making the mandatory transition into a swan. But in Richmond’s Cinderella ugliness seems to be immutably awful. It’s not just that spectators have three times to yell “oh no you’re not” when Ian Good and John Barr declare that they’re the beautiful sisters. Nor just that Su Douglas’s wicked stepmother is said at one point to be “so ugly she has to spike her own drinks”. Nor just that there’s a gibe at the Prince of Wales’s failure to be as handsome as Prince William.

No, it’s that, when I caught the show, Paul Zerdin’s Buttons picked on a chap in the fourth row, got him to admit that his name was Kevin, and kept twitting him as Ugly Kevin and, if I understood another slur, Boozy Kevin. And since Zerdin is a ventriloqist and as skilful as he’s jaunty, his dummy Sam got into the act too. Buttons: “Don’t tell Kevin he’s ugly.” Sam: “Why – does he not know?”

Well, I peeked at poor old Kev in the interval and he seemed a perfectly pleasant, sober bloke. As for Douglas, she’s as fine-looking as she’s scary. But, yes, the transvestite siblings are traditionally challenged: Good’s Grizelda is a big, lumbering blob and Barr’s Mona a scrawny squiggle whose hair has a habit of changing from purple to blonde or black to pink.

Well, I’m not going to get all PC about this. If there’s something in the Richmond air that creates an obsession with shapeliness, it’s a local problem, alongside traffic jams or low-flying aircraft. And its panto is, as usual, pretty good and, as usual, boasts a star or two: not only the excellent Zerdin but Nigel Havers, an affable Baron Hardup who convinces when he ruefully says he has a soft spot for his wife (“A swamp in North Wales?”) but doesn’t when he calls her fishface and starts ordering her about.

The other ingredients include a tiny pony for Lucy Newton’s comely Cinders, a ghost that looks like a blend of Klansman and octopus, one of the three Simon Cowell jokes I’ve heard this Christmas, dancing huntsmen, a rhyming fairy godmother, collective shouts of “Hiya, Buttons”, demands that we chorus what my notebook improbably claims is “umber, dumber, dooka, yeh!”, and old jokes. What, for instance, happened to Hardup’s brother’s fruit stall? Yes, it went pear-shaped.

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