Lion Boy. By Zizou Corder. Puffin pound;12.99 (hbk), pound;6.99 (pbk)

The Amulet of Samarkand. By Jonathan Stroud. Doubleday pound;12.99

Predator’s Gold. By Philip Reeves. Scholastic pound;14.99

I can understand why the fundamentalist Christians are getting worried. The Harry Potter phenomenon has revealed that most of our young people - those who can read, at least - instead of fixing their thoughts intently on this life or the next, are actually deep in fantasy realms battling forces of evil and warding off temptation. Rather like President Bush, in fact, but with less power.

Such preoccupation has traditionally been the lot of young bookworms, but as they used to be buried quietly in a book under a swottish exterior, no one noticed too much. Now fantasy thrillers, many laced with comedy, have bounded into the mainstream, with subsequent marketing opportunities, adults are forced to scrutinise their contents, with mixed feelings.

Unfortunately, some books on the fantasyadventure shelf are dull, formulaic, arch and repetitive. Lion Boy is a quest-based tale set in a nightmarish big-city future. With its talking animals, an ethnically diverse hero and friends and an anti-globalisation sub-plot it reads like PC Potter, but it lacks J K Rowling’s vitality and sense of fun. It’s a simplistic fictional universe: lions are furry friends, and inner-city drug dealers are bad. I found it demeaning to lions.

What a delight, on the other hand, is The Amulet of Samarkand. Jonathan Stroud’s cracker, the first of a trilogy (yes, more, please) following the adventures of a middle-ranking djinni in (another) dystopian alternative future London, is pure enjoyment from beginning to end. The sinuous plot, which involves plotting and counter-plotting to gain possession of the eponymous magic object, is of less moment than the verve and sardonic wit of Stroud’s narration, snapping between the points of view of Bartimaeus the djinni and Nathaniel the apprentice wizard. Each is a match for the odious other, with lots of sly allusions to Egyptian and Arab mythology to spice up the action.

Almost purely amoral, if not downright wicked, the character of Bartimaeus manages to convey the benefits of thoughtfulness, politeness and kindness by glorying in their converse. A tonic for anyone aged 12 and up.

Philip Reeve’s Mortal Engines was a ground-breaking futurama that envisaged a world in which all-out war had reduced humanity to living in mobile cities that roved the planet, consuming, manufacturing and trading with each other or gobbling each other up. As they made and broke alliances, the civilisations that remained place-bound launched sorties against them. A young Londoner, Tom, played a leading role in squashing one set of dirty tricks from city managers and met up with a disfigured aviator, Hester.

This new volume follows their adventures as they land in the half-dead city of Anchorage, meet up with unfinished business from their first adventure, are tempted by visions of a faraway haven in the Dead Continent (America), and wrestle with sexual jealousy.

It’s a real teenage book, sparking with altruism, passion and suspicion, shot through with remorse and regret, ending on an unresolved but optimistic note.

Literature like this is a perfect bridge from Potterland to books aimed at adults, and, again, a good read for 12 and above.