FOR MORE THAN 30 years, Eva Ibbotson's dazzling inventiveness has spanned comedy classics such as Which Witch and Dial A Ghost, plus more serious, prize-winning fiction such as Journey to the River Sea. One of the best-loved authors for readers of eight and up, her gorgeously eccentric witches, ghosts, orphans and explorers are an essential part of an enriched childhood; yet her own story, as a Jewish refugee from Vienna, sent at eight years old to Dartington Hall and exposed to a startling clash of cultures, has never been drawn upon. Now, in her eighties, she has produced The Dragonfly Pool.

Tally, its heroine, is a doctor's daughter growing up in the East End. It's 1939, and a grateful patient of her father has arranged for her to leave London on a scholarship to Delderton Hall, a progressive, co-educational boarding school in Devon, staffed by teachers almost as eccentric as their pupils. Here, “where the children would be free to follow their instincts and develop in a natural way”, and pupils don't have to go to lessons, Tally meets characters ranging from the abandoned daughter of a film star to an axolotl (salamander) called Zog.

Having been to a progressive co-educational boarding school myself, I always read novels about the jolly times had by boys and girls under the benevolent gaze of enlightened educationists with considerable scepticism. It's just possible that in the 1930s the innocent, bookish, kindhearted Tally would have survived and triumphed. The charming eccentricities of her kindly teachers will be familiar to admirers of Ibbotson's enchanting romantic novel for older readers, A Song For Summer (recently reissued by Young Picador), right down to the drama teacher who tells pupils to “practise giving birth to themselves”.

Once Tally and her new friends depart for the beleaguered kingdom of Bergania, The Dragonfly Pool becomes a different kind of story. The Deldertonians are going to perform a “flurry dance” in an international festival, and young Prince Karil, miserably isolated and bullied by his adored father's court officials, watches them with envy. Little does he realise that soon, Tally and her friends will be his only chance of escaping from an assassin and a dictator bent on taking over his country. When Tally and Karil meet by the secret dragonfly pool, it will change both their lives and the future of Bergenia.

Part of me is sorry that the whole novel did not take place at Delderton Hall, but only this author could have hitched the madcap world of progressive education on to a thriller involving not one but two daring escapes. As in all of Ibbotson's fiction, the enemies of the young and pure are the cold and snobbish, with Karil's intended bride, Carlotta, as someone children of 9+ will love to hate. One actually fears more for Karil in the home of his posh, pompous relations than at the hands of the Gestapo, and his final bolt for freedom will have young ones reading by torchlight.

Like Journey to the River Sea and The Star of Kazan, this is a tale as delicate and buoyant as anything filmed by Alexander Korda, blending comedy, history and tragedy with an irresistible wit and verve. Underlying Ibbotson's liberal, liberating plot line are profound questions about education, the price of being different, and the different kinds of prison that all individuals have taken care not to find themselves trapped in.

The Dragonfly Pool (9+) by Eva Ibbotson
Macmillan, £10.99 Buy the book here

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