Isn’t she the skinny twee primary school teacher who discovers what a brilliant little self-taught swot Matilda is?

No, that’s Miss Honey - “A beautiful oval face and so slim that if she fell over she’d smash into a thousand pieces like porcelain”. Trunchbull is headmistress of Crunchem Hall, a grotesque, fat woman in even bigger gym knickers who wears her hair in a bun and once threw hammer and shot put in the British Olympic team. She has no love for humanity but especially detests little girls.

But wasn’t she once a girl ?

“Not for long,” claims the Trunchbull. “I became a woman very quickly.”

Not exactly Estelle Morris though, is she?

With her bulging smock, scraped-back hair, tweedy plus-fours and huge leather belt, Roald Dahl clearly sees Agatha Trunchbull as a cliche of Monster Raving Lesbianism, ugly, man-hating, child-hating and particularly embittered against petite little prettikins like Miss Honey.

Isn’t he casting aspersions against those women teachers who are simply married to their career?

Give over, Trunchbull doesn’t give a damn about teaching. She regrets the passing of the days when she could use her belt to roast little girls’ bottoms but she does still have The Chokey - a narrow cupboard lined with broken glass and nails where children are locked up all day with no room to sit down.

Surely there’s something to be said for her?

Sorry, no. She’s a pug-ugly, marauding monster who bullies the staff, scares children to death and terrifies parents away from the school gates.

There, I said there had to be something

She’s also a firm believer in exclusion. Anyone who annoys her in class is thrown out - literally through an open window. Ask Julius Rottwinkle, who was ejected after being caught eating, or Amanda Thripp, whose mother put her hair in pigtails. They both landed on the playing fields.

What’s wrong with pigtails?

I told you, Roald Dahl sees Trunchbull as a caricature of the bitter lesbian who holds a particular animus against sweet-hearted creatures like Miss Honey whom she swindles out of the Red House (it should have been Honey’s inheritance).

I don’t suppose she finds true love and reforms?

No. Matilda uses her powerful brain to frighten the Trunchbull into doing a bunk and that leaves Matilda free to live in the Red House with Miss Honey happily ever after.

And the moral of the story?

Pretty teachers are nice and fat ones aren’t

Oh great