Kit Milcourt is 38 - lean, dark-browed, adventurous, and with a “quirky, crooked smile”. He has been a successful banker, but his young wife, Anna, has wooed him from the City into teaching. And indeed she was right. Like the Robin Williams character in the film Dead Poets Society, he is a brilliant English teacher, unconventional and unpredictable, a maverick loved by his pupils but hated, feared and resented by his systems-fixated acting head and (especially) his thin-lipped head of department.

He teaches with Anna in a struggling comprehensive whose only other distinction is a legacy that funds an annual educational trip to Europe. For Kit, given as he is to impromptu expeditions across winter playing fields to give his class an authentic sense of Pip’s Dickensian marshes, such a grant is too valuable to be missed, and the trip he has planned is the central feature of Libby Purves’s latest novel.

The destination is Venice, in February, with 15 initially reluctant learners from Kit’s Year 7 group and with Anna as the necessary woman teacher. But Anna falls happily and very sickly pregnant. At the very last minute - it’s that or cancellation, Kit is told - her place is taken by Molly Miles of the thin lips. Kit has told nobody, not even Anna, that he has chosen February because it’s carnevale week in Venice, and that he has packed all the Dracula costumes from the school drama store.

In the event the children are intoxicated as much by the city itself as by the sights and sounds of the masked carnival and they fill their diaries with intensely vivid echoes of the writers he has been reading to them. In spite of Molly’s palpable disapproval, the trip is a huge success.

But an accusation is made, quite unfounded, that gives the acting head an excuse to suspend Kit from his post pending routine child protection proceedings. Kit falls ill, and as his depression and Anna’s fears grow deeper, the mask of that quirky, crooked smile is stripped away and we begin to learn of the fears, that since his childhood in a repellently different sort of school, Kit has hidden within himself.

It all ends happily, of course. A love-sick schoolgirl withdraws her allegations, and the acting head’s admonitory noticeboards are covered with children’s petitions saying “We Want Big Bat Back”. But except to say goodbye, Kit doesn’t return. Indeed, he gives up teaching, so we never quite resolve the conundrum the story poses.

Who do we need most in teaching: the sticklers for syllabus and method, systems and order, or the risk-takers who ignore memos and despise prescription but take delight in opening the eyes and ears of children to the richness of language and of learning?

It’s in the nature of life, of course, and not just in fiction, that there is no one answer to that question. Still, the author leaves us in little doubt where her sympathies lie, and given her prominence in the media, that is one of two good reasons for ordering her book.

The other? Simply that it’s a good story, crisply and lightly told, that touches on many of teaching’s current preoccupations and dilemmas and that grows in depth as it unfolds. It would make an excellent Christmas gift - but be sure you read it first.