Some trilogies are open-ended. When the author decides to add a fourth book to it, we start to call it the So-and-So Quartet. Since fans of a series are unlikely to regret the arrival of a new installment, this sort of thing is usually embarrassing only to publishers who have invested money in packaging the first three books as the So-and-So Trilogy, and to unsparingly critical readers who notice (sometimes) that the fourth book isn’t quite as good. But what do we do when a trilogy comes to a very definite, final end—like, for example, the Bartimaeus Trilogy, whose human protagonist John Mandrake made the final sacrifice at the end of book three? (Oops. Spoilers!) How does the author get away with adding a fourth book to the series? It’s easy, actually. He makes it a prequel. And he makes it good.
Halli Sveinsson’s world has been shaped by heroes, but the time of heroes passed long ago. Still he yearns to be like his ancestor Svein, one of twelve legendary warriors who sacrificed their lives fighting off the Trows—a race of tunnel-dwelling, man-eating monsters who have not been seen since the slain heroes were buried with their swords.
Three present-day teens are thrown together in the last defense of a medieval castle—each one lonely for a different reason. Emily is an only child whose schoolmates either pick on her or ignore her. Simon is the youngest child of a big, blue-collar, trouble-making family, who often gets picked on at home. And as for Marcus… well, he’s not even from the West Norfolk village where the children sneak onto the grounds of a ruined castle for a bit of sledding and snowball-fighting.
In Book 3 of the “Bartimaeus” trilogy, a seventeen-year-old magician named Nathaniel, though he calls himself John Mandrake, has clawed his way nearly to the top of a world of (sometimes literally) backstabbing ambition. It’s an alternate-history version of present-day Britain, where magicians are the ruling class and the non-magical “commoners” toil in conditions not far above slavery.
If a boxed set of “Harry Potter” were to fall through the looking-glass, what came out the other side might be a lot like the “Bartimaeus Trilogy”, of which this is Book 2. The fantasy world in this series is somewhat of a bizarro, backward-land version of Harry’s wizarding world, which forms a secret enclave within the present-day world of us ordinary muggles. In Bartimaeus’ world, the British empire is openly run by magicians, while the majority of the population—dismissively called “commoners”—toils in a condition not far above slavery.