“Censorship!” shrugs Axel Scheffler. “It exists even in the world of the picture book, you know? Editors tell me I draw creatures with teeth and claws that are too sharp for little readers..

.” But both the 66-year-old German illustrator and Julia Donaldson – the author with whom he is most closely associated – know that the most potent children’s fiction has always been red in tooth and claw. It’s the jagged jeopardy of those fierce features that draw small children to their most famous creations: The Gruffalo (1999), Zog (2010) and The Highway Rat (2011).

Sometimes Scheffler’s spikes give a dangerous edge to the soothing flow of Donaldson’s rhyming pentameter. Sometimes his childlike googly eyes bring the safety of silliness into some of Donaldson’s darker plot points. Dubbed the Lennon and McCartney of the preschool library, the duo have sold millions of books, many of which have since been turned into BBC animations broadcast every year on Christmas Day.

The last – an adaptation of their 2019 spin on Romeo and Juliet , The Smeds and the Smoos – went out just before the King’s speech and was watched by 8.1 million households. But like the Beatles, Donaldson and Scheffler are frank about their creative friction.

Donaldson famously objected to the way Scheffler drew a character’s breasts when they first worked together on her book A Squash and a Squeeze (1993). Today Scheffler admits he objected to the “lack of zoological precision” in their .