When a twelve-year-old evil genius tries to restore his family fortune by capturing a fairy and demanding a ransom in gold, the fairies fight back with magic, technology, and a particularly nasty troll.

"Teenage genius Artemis Fowl and his arch rival Opal battle to the last in this eighth and final book in series"--Provided by publisher.

"Twins Myles and Beckett face off against Lord Teddy Bleedham-Drye, the Duke of Scilly, who has been plotting revenge against them since they humiliated him"--

Artemis's mother has contracted a deadly disease -- and the only cure lies in the brain fluid of African lemurs. Unfortunately, Artemis himself was responsible for making the lemurs extinct five years ago. Now he must enlist the aid of his fairy friends to travel back in time and save them. Not only that, but he must face his deadliest foe yet...his younger self.