Tumtum and Nutmeg, by Emily Bearn and Nick Price
Egmont, £5.99

Barnaby Grimes: Return of the Emerald Skull, by Paul Stewart and Chris Riddell
Doubleday, £8.99

CHILDREN ARE fascinated by rodents. The film Ratatouille is only the latest in a series of fictions about them. Miniature saviours of the small, the powerless, the imprisoned, rodents, from E.B.White's Stuart Little to Margery Sharp's The Rescuers, are childhood's champions. They dare to venture into the territory of giants, where their speed and smallness can be turned to advantage. The parallels with small children are obvious, but adults, too, were viewed in Gulliver's Travels by the gigantic King of Brobdingnag as “the most pernicious race of little odious vermin that nature ever suffered to crawl upon the surface of the Earth”.

We can, in other words, learn about mankind from mice. In Emily Bearn's enchanting debut, Tumtum and Nutmeg, Arthur and Lucy Mildew are two children in serious need of attention. Their mother is dead and their father, though loving, is an absent-minded inventor living on thin air while his children “eat horrid gloop out of tins in their icy kitchen”.

Two kind-hearted mice, Tumtum and Nutmeg, watch in dismay because their own home, hidden behind a heavy dresser, could not be more different. Nutmouse Hall is a haven of domestic bliss. So the two mice decide, much in the manner of Beatrix Potter, to help the children by mending their clothes, heater and hopes. Like Potter's Two Bad Mice, they even use the doll's house as a temporary base, but instead of trashing it they clean it.

Into this charming idyll comes Aunt Ivy, her five suitcases and her horror of mice. She will stop at nothing to get rid of them, and soon spots the presence of Tumtum and Nutmeg as they try, heroically, to continue their ministrations. A battle of wills begins.

Good new books for children of 5 to 8 are rare, and this is one of them. Bearn's style is as crisp and warm as a home-baked biscuit. She understands both the passion most children share for miniature worlds and people and their need for comfort to be contrasted with the mildly grotesque.

Alas, the cover, which shows Nutmeg in a pink dress, will be instantly rejected by any self-respecting male, and the illustrations are too coarse. I'd also have liked the children to have learnt a bit more self-reliance by the end, because even very young children quite enjoy doing housework.

The indefatigable Paul Stewart and Chris Riddell are just the ticket for boys of 9+. Their latest series is about Barnaby Grimes, a “tick-tock lad”, or messenger boy, who gets involved in gruesome Gothic adventures. Like Philip Pullman's Spring-Heeled Jack, they are set in the vaguely Victorian maze of London - though Return of the Emerald Skull is actually more about a school as sinister as Anthony Horowitz's Groosham Grange. Barnaby's zest, verve and just the right amount of cynical humour, accompanied by Riddell's exquisitely elegant illustrations (above), makes for splendidly spooky, sophisticated tales. An ancient Aztec skull is making the boys of Grassington Grange behave like those in Lord of the Flies, (“Hunt the hog!” they cry, pursuing the games master) and Barnaby must break the spell.

What is especially pleasing about Barnaby is that there is not a trace of self-pity in him. Rejoicing in his independence and armed with a swordstick and sharp wits, he is joined by Mei Ling, a tiny, beautiful Chinese girl who does martial arts and meditation. Mousy behaviour can take you only so far in the lumbering world of giants.

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