The blurb on the back:

On his first murder case, a brilliant schoolboy is swept into a perilous adventure!
When his friend the professor mysteriously dies, sixteen year-old Holmes suspects foul play. The eager detective drags his new friend Watson through London's dark alleys and over the rooftops, braving disaster - and even death - to capture a tricky, powerful foe!

opening lines:
One night during the winter of 1870 a wealthy London accountant of exemplary character leapt to his death though a third floor window at his apartment in Pimlico.

This is rubbish, an insult to you and an affront to me. Just to be clear why (briefly, cos I can't be bothered to go into all the details):

• The story is told by Watson but we get descriptions of events at which he wasn't present and to which all the witnesses died without passing on their experiences. In other words, Alan Arnold doesn't understand the basic principles of a first-person narrative.

• The story flatly contradicts key elements of the canon - to take one obvious example: Holmes and Watson did not meet at school (still less at that Blairite institution, the Brompton Oratory).

• Arnold's concept of relating this to the canon is simply to lift huge chunks and drop them at random into his story.

• It's full of extraneous rubbish designed for TV-obsessed kiddies too thick to read the original stories: there's a cute dog owned by a cute girl, with whom Holmes is in love (the girl, sadly - if it was the dog, we might be onto something).

Obviously, most of this is the result of letting Hollywood interfere with the classics: with Steven Spielberg as producer and Chris 'Home Alone' Columbus as writer, it's not too surprising that the story is stuffed full of clichés and nonsenses aimed squarely and very, very simply at Middle America - you wouldn't expect any ambiguities from this lot and you don't get them.

Now in the movie, all this wasn't quite so disastrous. Barry Levinson is a good, competent director, the acting - Nicholas Rowe and Alan Cox as Holmes and Watson - was really quite good and if the plot was a bit ropey (well, very ropey) then it didn't matter too much because Sherlock Holmes is never just about plot. And anyway, dropping quotes from the real books into a movie can come across as a bit of a post-modernist joke in the right hands.

But when it's put down on the page, the whole thing turns into a catastrophe of the first water. Alan Arnold was the publicist on the film (the publicist!) and is clearly incapable of writing a novel. 'My feeling throughout,' he says in the Acknowledgements, 'has been one of the deepest respect for the writings of Sir Arthur Conan Doyle.' If he had any self-respect, he would have given up on the project once it became painfully apparent that he wasn't up to the job. In a civilized society, he and Columbus would be taken out and shot for their crimes against Sherlock. A single soft-nosed revolver bullet fired from a converted air-gun should be enough for both of them.