When demons begin appearing on Earth unpredictably, foreshadowing a cataclysmic breakdown of their magic, Artemis and his friends face a new foe--a twelve-year-old girl whose intellect just might match Artemis's own--as they try to prevent catastrophe.

Opal Koboi, power-crazed pixie, is plotting to exterminate mankind and become fairy queen. If she succeeds, the spirits of long-dead fairy warriors will rise from the earth, inhabit the nearest available bodies and wreak mass destruction. But what happens if those nearest bodies include crows, or deer, or badgers -- or two curious little boys by the names of Myles and Beckett Fowl? Yes, it's true. Criminal mastermind Artemis Fowl's four-year-old brothers...

Taking the Fowl jet without permission before it mysteriously explodes over Florida, the Fowl twins are placed under house arrest until Myles's questions about what really happened lead to an astonishing abduction.

In the late nineteenth century, when Conor Broekhart discovers a conspiracy to overthrow the king, he is branded a traitor, imprisoned, and forced to mine for diamonds under brutal conditions while he plans a daring escape from Little Saltee prison by way of a flying machine that he must design, build, and, hardest of all, trust to carry him to safety.