Jack’s world measures eleven feet by eleven feet. He shares Room with TV and Bath and Meltedy Spoon and Rocker and, of course, with Ma. Oh, there’s Dora, too, who lives in TV and goes exploring with him. But she isn’t real. Then there’s Old Nick, who comes in some nights to make Bed creak with Ma. He has to hide in Wardrobe those nights, because Old Nick can never see him. Jack’s not sure if Old Nick’s real or not. Maybe…he becomes real when he comes into Room?

This is the world of Room, the new sure-fire bestseller that crept onto the Booker longlist before it was even published, and has already been installed by the bookies as joint favourite to win. Describing the world of a child born into captivity from that five year-old boy’s perspective, it catches a kind of zeitgeist that emerged after the Josef Fritzl case. Just in case you had any doubts about the sign of destiny hanging over this book, it comes complete with glowing recommendations from some of the best-selling authors of the modern era.

What do they say? Well, here’s the view of Audrey Niffenegger, who wrote the Tesco 3-for-2 paperbacks staple The Time Traveller’s Wife: “Room is a book to read in one sitting.” This is precisely my problem with it. You should not be able to digest a potentially Booker-winning novel in a single day. The book recently voted “Booker of Bookers,” Midnight’s Children, took me two weeks. Even last year’s overrated winner Wolf Hall took six days.

Am I dismissing Room just because of an inborn snobbery about thrillers? Absolutely. The purpose of the literary novel is to challenge its readers, to make them swallow difficult truths, to make them think really, really hard. Whereas when you read Room your heart pounds, you cry a little bit if you’re a girl, and when you finish you look at the world around you and think “well thank God I’m free.” And then you forget all about it.

Room is not stupid. Emma Donoghue has put a huge amount of imaginative effort and sympathy into writing it, and it is hardly ever as mawkish as it ought to be. There are several scenes where she uses Jack’s five year-old eyes brilliantly. The satire on the media is clever, especially when Oprah interviews his mother, and in another scene when a group of sofallectuals are discussing Jack’s case:

“There’s a woman, too. ‘But surely, at a symbolic level, Jack’s the child sacrifice,’ she says, ‘cemented into the foundations to placate the spirits.’

“Huh?

“Grandma comes in and switches the TV right off, scowling. ‘Those guys spent too much time at college.'”

But in spite of all this, Room is intellectually shallow. It’s very much like Mark Haddon’s The Curious Incident of the Dog in the Nighttime, but with captivity in place of Aspergers Syndrome. I would go so far as to say that it would not be on the Booker longlist at all were it not for our ghoulish fascination with the Fritzl case. If Room beats Peter Carey’s Parrot and Olivier, something is profoundly wrong with the way the nation reads books.