Artemis Fowl and the Lost Colony (Book 5)

Demons are beginning to materialize without warning on Earth. If humans were to capture one, all fairies would be exposed. In order to protect themselves, the fairies must decipher complicated equations to determine where the next demon will appear. Not even the brilliant Foaly can make heads or tails of the formulas but he knows someone who can: Artemis Fowl.

Softcover. English. Puffin. 2006. 376pp. In good condition.