In this sequel to The Opal Deception (2005), 14-year-old Artemis discovers an unraveling time tunnel connecting demons with the earth. These imps have sworn revenge on humans, and their unpredictable appearances threaten to expose the entire fairy world. As always, Colfer delivers not only continuous action but also witty wordplay and dialogue, understated humor, and plenty of magical technology and gadgetry. A must for kids who have enjoyed Artemis' previous escapades.