One of the wonderful things about the Harry Potter phenomenon is that it helped the world wake up to something we insiders had always known: the wild and endlessly delightful world of imaginative literature. To those of us who grew up on Ursula K. Le Guin, Arthur C Clarke, J. R. R. Tolkien and the like, the Harry Potter books were a welcome addition to a beloved genre, fitting in happily with Diana Wynne Jones and Jane Yolen, but with their own variations on the theme. But also, the Phenomenon opened a wide window in the wall that normally separates the ghetto of imaginative literature from its ultra-respectable cousin, mainstream realist fiction. The Mundanes on the other side of the wall actually peered in and showed some interest.   The Phenomenon has given rise to many an imitative attempt that we could have done without, but it has also created room for an explosion of imagination amongst writers of fantasy and science fiction, who are now (if they are any good) assured of a large audience. Among the new and unique voices is that of Eoin Colfer, whose Artemis Fowl books are amongst the most popular currently being published in the genre. I began by reading the last book in the series, The Opal Deception, and followed it up with an unrelated book by Colfer called The Supernaturalist.   Despite not having met the main character, a teenage boy with the unlikely name of Artemis Fowl, in earlier books, I was immediately drawn into the world of the story. A pixie lies in a coma in a world that lies deep under our own, a world populated by fairies, elves, dwarves and the like. None of these characters are cutesy; the pixie is evil incarnate, placed in protective custody by the fairies, some of the elves are unpleasant and the dwarves have disgusting personal hygiene. Above this world, modern human society pursues its course in its usual oblivious manner, and among the few humans who know about the hidden world below is our hero, Artemis. He is a criminal mastermind (but not evil) — he puts his brain to various illegal tasks for the pleasure of it, and for greed. Like most products of urban culture, he’s the ultimate consumerist, wanting more toys, power and valuable things. Imagine a spoiled, ambitious, brilliant kid who can get whatever he wants through his brains ...