Ever since his brilliant debut collection, The Quantity Theory of Insanity, Will Self has occupied a peculiar and somewhat frustrating position. A fantastically inventive writer of short stories, he has never, quite, pulled off a novel. With the exception of My Idea of Fun – strange, twisted, and extraordinarily funny, but not really a novel, though God knows what it was – his full-length outings look more like short stories stretched to breaking point. They might have been entertaining to read, but all were propelled by the same short-haul motive force that distinguished his stories: a good pub conversation; a funny joke; a neat conceit.

But with this one, by jingo, I think he's got it. In The Book of Dave, he has hit on a conceit rich enough to carry a narrative of nearly 500 pages, and he has mined it assiduously, imagined it fully, and given it a plot and a structure equal