Harry Potter's Lonely Hearts Club Band?

The good news is that while not abandoning her idiom, in The Goblet of Fire JK Rowling has allowed herself to drift loose of these moorings and evolve Harry's world: the wizarding universe is significantly different at the end of this book than it was at the beginning. You couldn't say that about the first three.

With each book Rowling has developed her literary aspirations: the Goblet of Fire is pretty baroque compared to the roughly-hewn Philosopher's Stone. I think she manages to stay the right side of the self-indulgence line, though: it remains to be seen whether Rowling can resist the temptation to stray over it next time round.

Rowling's instinctive gift for storytelling is generally absorbing but is by no means perfect: at the end there is some fairly ham-fisted dialogue that exists only for plot exposition. While she isn't the first writer to lean on this particular shovel (Conan-Doyle's Dr Watson character existed almost exclusively to allow Sherlock Holmes to explain parts of the plot Conan-Doyle couldn't be bothered setting out properly) this doesn't mean it isn't a flaw. Ultimately Harry Potter is a wonderful creation, and such sales are an achievement which cannot be explained away as a product of canny marketing or sheer fluke. But this early on, nor can you properly gauge how Harry stacks up against Bilbo Baggins or Aslan the Lion. To my way of looking at it, that's the real test.