Tethered on a silken leash, a green dragon with the wing markings of a wartime spitfire is skewered by the diagonal thrust of St George's lance. The dragon's jaw gapes, echoing the mouth of the cave beyond, a storm brews in the sky and an anxious princess looks on helplessly.
Meanwhile, in another part of the forest, as they say, a satyr leans tenderly over the lifeless body of a young woman. Balancing the composition to frame a distant lyrical landscape, a large dog looks on mournfully.
Elsewhere you can find a mouse in an apron busily washing up in a chaotic kitchen, a monkey striding along carrying a mountain on his head and, in the distance, a steam train, driven by a small boy and a dog, which crosses a bridge in an atmospheric haze of steam and speed.
These pictures, by Paolo Uccello, Piero di Cosimo, Gabrielle Vincent, Michael Foreman and John Burningham respectively, are just a few of the intriguing images put together by Quentin Blake at the National Gallery. With such a rich diversity of artists, this is obviously no ordinary exhibition.
When Blake became our first Children's Laureate in 1999, his job was to raise the profile of children's books. Alongside his own work he has involved himself with countless lectures, interviews, publications, personal appearances, book events and now, at the end of his two years (a new Laureate will be chosen in May), his most ambitious project of all - this exhibition, enthusiastically supported by the National Gallery.
His aim, he says, is to bring together the worlds of fine art and illustration in a way that will allow children to relate the paintings they might see in the great galleries to the kind of art they are familiar with in picture books, and to encourage them to explore pictures for themselves without preconceived ideas about what's "famous" and what they should like; without complicated information about dates and academic interpretations.
All you get here is the picture (but not the title) and the name of the artist. The effect is magically liberating. It doesn't matter if you've never heard of Uccello, Daumier, Edward Hopper, Elsheimer, Goya or Ken Kiff. The idea is to look and let the imagination take over. Children can be forthright critics, and on the National Gallery website, there's a chance for them to write their own stories about the paintings.
It will indeed be fascinating to see children's reactions to work such as Pietro Longhi's almost surreal painting of a group of masked Venetians inspecting a rhinoceros, or Paula Rego's huddle of sleeping girls, or that nightmarish cloaked figure by Goya. And what's inside those little suitcases carried by Jozef Wilkon's moonlit bats?
And in Emma Chichester Clark's painting, what are the gifts offered by the young woman whose spindly figure echoes that of Uccello's princess? With access to the whole of the National Gallery, and such a vast choice of contemporary illustrators, how did Blake choose? "I wanted pictures which had about them a sense of story - a sense of 'what's going on here?' There had to be something graspable to suggest a story, but nothing too obvious - the Pre-Raphaelites, for example, are too easily decoded."
Having created a friendly welcome with his own drawings (he was delighted to be allowed to draw all over the walls) he's put the 26 pictures in alphabetical order, thereby limiting the exhibition to a manageable size and "doing away with any sense of hierarchy".
As with any finely tuned personal anthology, subtle juxtapositions here strike some surprising sparks. From the first picture by Hendrick Avercamp, in which the eye zigzags like a skater through a wintry scene full of incident and activity, to the final delicious watercolour by Lisbeth Zwerger, which features a mysterious cookery demonstration, this promises to be a thought-provoking, often challenging and richly rewarding adventure.
Children let loose here will have the opportunity to find for themselves pictures that will probably remain their friends for life. Tell Me a Picture is in the Sunley Room, National Gallery, London, from February 14 to June 17.
An interactive section for children on www.nationalgallery.org.uk invites submissions of the stories behind the pictures.
School groups can book free "Stories Through Pictures" talks during visits. Tel: 020 7747 2424.
There are also free storytelling events for families during half-term (February 19-23) and on Saturdays throughout the exhibition; a Quentin Blake lecture for children and adults at 2.30pm on March 10 (pound;3, pound;1 under-12s); and a series of lectures for adults (pound;3 per lecture) featuring author Russell Hoban, composer Mark Anthony Turnage and authorillustrator Anthony Browne. Tel: 020 7747 2885.
An accompanying book, Tell Me a Picture (Frances Lincoln in association with the National Gallery pound;9.95) gives details of the 26 pictures.
Baker's Dozen, an exhibition of the work of 13 book illustrators chosen by Quentin Blake and Irene Edwards, is at Bury St Edmunds Art Gallery, Suffolk, March 6-April 11. Tel: 01284 762081. www.burysted-artgall.org