The Earth is in the grip of a new Ice Age, and when twelve-year-old Eleanor's scientist mother disappears in the Arctic, Eleanor sets off on a dangerous journey to find her--and uncovers a mystery, a crime, and evidence that Earth has been visited by extraterrestrials.
On the eve of the French and Indian War, Billy Bartram and his naturalist father travel into the American wilderness in an airship--pursued by a party of French soldiers and haunted by a terrifying bear-wolf--on a quest to find the lost kingdom of the Welsh prince Madoc.