Artemis Fowl 04 and the Opal Deception

Artemis Fowl and the Opal Deception is the fourth phenomenal book in the legendary Artemis Fowl series by Eoin Colfer.
Arch-Criminal Artemis Fowl's mind has been wiped. Now someone wants him dead.

Artemis Fowl is the only boy ever to have discovered an armed and dangerous fairy race living below ground. He just can't remember any of it.

But Artemis needs his memory back - and fast - because a power-crazed pixie is out for revenge, secretly scheming to overthrow the Lower Elements Police. If only Artemis's one fairy ally, Captain Holly Short, wasn't on the run. Everyone is depending on him.

And with Holly gone, Artemis is depending on a flatulent dwarf. Things are about to explode . . .