As the Grand Old Man of British letters and unofficial Writer Laureate, it is fitting that Alan Bennett should have chosen the Queen as the subject of this story. Not that this is his first foray into royal subject-matter: the Madness of King George was a successful play and film. But George III is a dead and gone figure of history. The Queen is very much alive, and writing a fictional piece about a well known public figure is quite a different proposition. The result, however, is an absolute delight.

The premise - and this is no more than appears on the dust jacket and summaries - is that the corgis wander off and the Queen, in hot pursuit, follows them into a mobile library parked at the back of the palace. Persuaded to borrow a book, one thing leads to another and she becomes an avid reader. It is the consequences of this new-found interest that form the focus of the story.

The first scene of one and a half pages is worth quoting from as it sets the tone and lays the themes for what follows. No more quotes after this, though; I don't want to spoil it for you.

The scene is a state banquet for the President of France.
The Queen: "I've been longing to ask you about the writer Jean Genet." [Pauses for the national anthems]. "Homosexual and jailbird, was he nevertheless as bad as he was painted? Or, more to the point ... was he as good?"

Unbriefed on the subject of the glabrous playwright and novelist, the President looked wildly about for his Minister of Culture. [...] The President put down his spoon. It was going to be a long evening.

And I thought, it's going to be a lovely read. I like to think that Bennett got his inspiration from watching one of these state occasions and wondering what on earth they talk about. This opening tells you what's coming. Humour, of course. Witty, incisive, a light touch, but barbed. Not the humour of an angry young man flinging satirical thunderbolts at the establishment but finding its targets nevertheless. And the targets: royal protocol, expectations of royalty, fear and suspicion of "high culture", the power of books to change an individual. More themes for satire are added later: mass market fiction, politicians and civil servants, treatment of the elderly, and if there's a common link, it's that we make assumptions about people based on our expectations of them.

That's a lot of content for a small book, and small it is. At 120 pages it's a novella in length but not format. From the opening vignette, to the final set scene with its long speech by the central character, the action proceeds episodically as if in a play, and there are some wonderfully comic set pieces The impact is also conveyed mainly by vocal interaction between the characters. No surprise there: it's as a playwright that Bennett is known.

But how do you put words in the mouth of the Queen? The Duke might at first seem a more promising mouthpiece but he only gets a bit part. The point is that she is a completely blank page. We know everything of her, but nothing about her - a perfect canvas on which to paint increasingly complex swirls of ideas, emotion and growing self-awareness. At the same time the "voice", even if fictionalised, has to be authentic, and Bennett with his superb ear for dialogue pulls this off brilliantly. This is the author of "Talking Heads", a collection of monologues which ran on TV at the end of the 1980s, in which a single speaker by apparently innocent remarks about an everyday situation reveals his innermost thoughts. The Queen speaks in short sentences, very direct, at times quite tart, eschewing jargon and metaphor. There is inevitably some use of "one" although that phases out as she discovers her individuality. And it's not just the Queen; all the other characters are perfectly captured, characterised and indeed caricatured through their speech. No names are named, but it's always clear who is intended. We do not need to be told which Prime Minister is being referred to.

But if the Queen is the main character, books are the stars of this show. Or, more specifically, reading books. "Books Do Furnish a Room" was the title of an Anthony Powell novel (which doesn't figure here) and that has been the Queen's relationship with them up till now. The distinction is frequently drawn between the ability to read and actually reading. Plus, of course, Bennett gets to have fun with selecting the books and authors with which to "furnish" his Queen. What would you choose, given a reading virgin Queen to select for? The picks are an eclectic mix but the effects he ascribes to the new reader are increased self-awareness, new depth of emotions and heightened sensitivity. Truly mighty pens indeed. Are we really the sum of the books we have read, or does it only work if we have not acquired these emotions elsewhere? As the Queen becomes more "normal" she becomes less queen-like. She crosses the divide into empathy and leaves monarchy behind.

Book selection is a tricky business. Even if you don't buy into the idea that books have the life-changing effect they have here, your choice of reading matter still says a lot about you, and Bennett is openly derisory about popular choices such as Andy McNab and Harry Potter. Of course, although from impeccable working-class roots, and a professional Yorkshireman, he is nevertheless a huge intellectual snob. Even the vocabulary he uses, such as "glabrous" quoted above (= bald, to save you looking it up, as I had to) sets him apart from the average bestseller paperback writer. On the other hand, he is also fairly scathing about the literati and it's interesting that the Queen learns nothing from them. They are all too self-absorbed. Her early guide, before she finds her own way, is a kitchen boy who is universally mistrusted by the palace establishment, and who fits in with neither the palace nor the literary world. Who does that remind you of? And it's also a position the Queen is heading towards. That's what books do for you.

Finally a memo to publishers. There is a credit crunch on, and a £6.99 cover price for a 4½" x 7½" paperback of 120 pages of largish print is a rip-off. It's so small I had difficulty finding it on my shelves when I wanted to look something up for this review. The last book of Alan Bennett's I read, a hardback version of Untold Stories, was so heavy it made my wrists ache, so there's no lack of material which could have been included to make a longer volume. One or two of his Talking Heads monologues would have sat very well with this story. Amazon sells it for £3.68, and I got it for £2.99 when it was a Times book of the week recently, but even so I would suggest trying your local library, if they still stock books.

This quibble aside, it is definitely recommended. A short read, but a happy one!