Artemis Fowl: The Last Guardian by Eoin Colfer

This book starts with a bang--and Artemis and Holly and the gang quickly realize that they'll need to act fast and use any help they can get to stop Opal Koboi's plan to kill all humans aboveground. For the most part, this book was similar to the other Artemis Fowl books: entertaining but not great. I though the ending was a huge copout, but I hesitate to say more so as not to spoil anything.