Jamie Thomson's Dark Lord: The Early Years gets right down to business: an unnamed narrator suffers a million agonies, while calling out for his hellion lieutenants to aid him, and we quickly learn that this is the Dark Lord, feared and tyrannical ruler of a distant kingdom, and that he has been transported to a suburban parking lot in our world. And that he's been put in the body of a child. Before you can ponder this conundrum for too long, he's in the custody of child services, in hospital, and is being treated as a delusional car-accident victim whose fantasy of being a mighty and merciless sorcerer/warrior are the desperate gambit of his amnesiac psyche. The well-meaning child psychologists deliberately mishear his name ("Dark Lord") and dub him "Dirk Lloyd," and place him with a foster family while they sort things out. And we're off to the races.
Dark Lord plays out this scenario with perfect deadpan humor (the book just won the Roald Dahl Humour Award). Dirk's foster brother and schoolmates are at first bemused by his insistence on his true identity and his penchant for tenting his fingers and bellowing mwa-ha-ha, but Dirk is a tactical genius who knows how to humiliate bullies with a few well-chosen words, how to make himself a king among jocks with shrewd assessments of kids' weaknesses; how to break teachers' grip on their classes with cutting remarks. His friends play along with his "Dark Lord" game, let themselves be called his "court in exile," but no one really believes that Dirk is really an interdimensional Darth Vader.
But Dirk is (probably) not delusional. At least, the author is very careful not to collapse the possibility one way or another, until just the right moment. This is wickedly funny, brilliantly told stuff, and you'll never have more fun cheering for evil.
Brits may already be familiar with this book — it was published more than a year ago in the UK under the slightly different title Dark Lord: The Teenage Years (there's also a UK sequel that came out last March called Dark Lord: A Fiend in Need — presumably a US publication will follow).