With Esio Trot coming to BBC One on New Year's Day, we've got some incredible insights into how Roald Dahl wrote this lovely story
In the meantime, we've been searching through our wonderful archive (housed at the Roald Dahl Museum) - which is where we store all Roald Dahl's letters, manuscripts, early drafts and much more - to find few gems that shed some light on where, exactly, Roald Dahl got the idea for Esio Trot...
Esio Trot was published in 1990 - it was actually the last of his children's stories to be released in Roald Dahl's lifetime - but interestingly the inspiration came a lot earlier.
In a speech delivered to students from Wright University, Roald Dahl told them how, when visiting his daughter at her London flat, he saw that her downstairs neighbour Mrs Shrimpton had a tortoise she kept in a box on her balcony.
Knowing a thing or two about tortoises (he had one of his own, which was then 16 years old), Roald Dahl began thinking about how slow they grow...
From this germ of a thought, his own story grew slowly too, until, 12 years later, it became Esio Trot.
When he'd finished writing the story of Esio Trot, Roald Dahl spent some time trying to get the title right. This page from a June 1989 draft shows him playing around with other ideas, including "THE MAGIC TORTOISE" and "THE WONDERFUL TORTOISE."
Having had 12 years to think on it, Roald Dahl knew exactly how much Mr Hoppy would have to 'grow' Alfie each time he made a switch: exactly two ounces.
So he created specific instructions for the illustrators - complete with his own sketches...
The other important part of Mr Hoppy's plan involved a clever tortoise-catching device - and again, Roald Dahl had very specific ideas about what this should look like. He even sketched out his own instructions, which look remarkably similar to the published illustrations.
Esio Trot comes to BBC One on New Year's Day. Watch the trailer here.
From January, you can also view the archive material for yourself along with props and costumes from the BBC One film at the Roald Dahl Museum.
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