He is hairy. He is horned. He has a touch of Hieronymus Bosch and Maurice Sendak. He wouldn't look out of place on a Gothic spandrel with a water-pipe busting from his oesophagus. He is the sort of shaggy, saucer-eyed, taurine, tusked monstrosity that the protagonists of a Dennis Wheatley novel might conjure up at a Satanists' cheese-and-wine party. All this and - to quote his co-creator - knobbly knees, turned-out toes and a poisonous wart on the end of his nose.
But legions of children are besotted with the Gruffalo and the book that bears his name - the rhyming tale of a wily mouse who scares off predators by inventing descriptions of a fearsome arboreal beast - which he is then rather surprised to encounter face-to-face.
According to the figures that splurge from his publishers, the Gruffalo has shifted 2 millions books worldwide. Sales in the UK have topped 600,000. A stage adaptation has toured the US and been committed to video by Andrew Lloyd Webber's Really Useful Group. Readers write to the monster's creators to tell them about the Gruffalo hunts they've pursued in their local deep dark wood, the Gruffalo costumes they've assembled from egg boxes and papier-mâché and dismembered jumpers, the home-made Gruffalo birthday cakes on which they've blown out the candles. The story has been translated into 26 languages. (In French editions, the Gruffalo's assertion that he will eat the mouse "on a slice of bread" has become "sur un lit d'artichauts".) And with yesterday's publication of the sequel, The Gruffalo's Child, it'll probably happen all over again.
This publishing phenomenon is a product of a long-distance collaboration. Julia Donaldson, a fifty-something author and songwriter who lives in Glasgow, supplied the Gruffalo's words. Axel Scheffler, a German-born illustrator resident in London, provided the illustrations. Writer and artist were paired by their publisher, Macmillan, and rarely meet, except at awards ceremonies. Indeed, Scheffler professes, "I don't know if we would have been friends if we hadn't been put together."
"I didn't really have a preconceived idea of what the Gruffalo would look like," reflects Donaldson. "It just came into being according to what rhymed with what." Until he actually appears, the beast is simply a jumble of disconnected physical characteristics: "His eyes are orange, his tongue is black/ He has purple prickles all over his back." Leafing through the notebook in which she wrote her first draft, Donaldson discovers that Gruffalo physiognomy might just as easily have encompassed spikes, trails of slime, or a pair of orange wings. "I think I originally envisaged him as being more weird and less furry. Before I had a publisher for the book I would tell the story in schools and ask the children to draw the Gruffalo. On the whole, theirs looked more like aliens and less like cuddly animals."
Gruffalo fans will get their first ever glimpse of what might have been at an exhibition of Scheffler's preparatory work and finished drawings in London later this month. The show offers new insights into Gruffalo evolution. In some sketches, the beast has more obviously Beelzebub-ish characteristics. ("There was a point," explains the book's editor, Alison Green, "when the Gruffalo was a bit more humanoid, but we decided that to make him a kind of troll wouldn't really work. He was really a woodland creature, a predator.") In some sketches, he also appears to be wearing a T-shirt and pants - and the mouse, too, it seems, once had a jaunty, green-striped rugby shirt, frock-coat and breeches in his wardrobe. This, claims Donaldson, was the product of a linguistic misunderstanding. Scheffler, she says, read her line "the mouse looked good", and jumped to the wrong conclusion. "He thought I meant good as in stylish, rather than good to eat." The artist, for the record, denies the story flatly.
The production of the sequel filled the boardrooms of Macmillan with serious debate about the nature of Gruffalo culture and society. Images of a whole synod of the monsters crouching in a cave were rejected: we see only the original Gruffalo and his daughter. (Donaldson speculates, rather shockingly, that the mother walked out on the family after an affair with another of the species.) Long discussions were held over the question of whether the junior Gruffalo should wear a bow in her hair. "My boss was very keen on this," reveals Green, "because she was thinking if there was ever a Gruffalo's child toy, it would be a good way of telling them apart. We felt, though, that they shouldn't be accessorised." This was nothing, though, to the huggermuggers that went on at editorial meetings about the cover of the forthcoming CD spin-off, The Gruffalo Song and Other Songs. Scheffler had completed a magnificent picture of the beast strumming on a guitar before he concluded that Gruffalo technology would have been incapable of producing such an instrument.
So what kind of relationship do the Gruffalo's creators have with the monster they have created? Scheffler's doodles suggest some ambivalence on his part. The Gruffalo sits, grinning, on the artist's desk, preventing him from getting on with his work; the Gruffalo torments the artist as he lies in bed, squatting on his chest like the furry demon in Henry Fuseli's The Nightmare; the Gruffalo bears down on the artist's head, upsetting his pots of ink. Somewhere, you suspect, Scheffler entertains the fantasy of kebabing the Gruffalo on one of his own tusks. (In his later years, it is said, E H Shepherd entertained belligerent thoughts towards Winnie the Pooh.)
Donaldson is happy to be asked about the creature wherever she goes - though it's far from being the only thing on her CV. She wouldn't recognise writer's block if it leapt out of a tree and threatened to bake her under a pie crust. She has five other books out this year: a book of action rhymes for young children; a parable about the symbiotic relationship between a hermit crab and a sea anemone called Sharing a Shell; a volume of poetry called Crazy Mayonnaisy Mum; an adventure story that teaches you how to count to 10; and a novel, The Giants and the Joneses, freshly optioned by Warner Brothers. All the same, she sounds rather triumphant when she tells me about her recent appearance at the Edinburgh Book Festival. "Do you know," she says, "we got through the entire event without anyone mentioning the G word."
'The Gruffalo's Child' is published by Macmillan, priced £10.99. The Gruffalo Exhibition of Illustrations by Axel Scheffler is at Waterstone's, 203 Piccadilly, London W1, from 11-27 September