Ten-year-old Leo's future and the fate of the extraordinary Whippet Hotel, where his father is the maintenance man, are at stake when a series of cryptic boxes leads Leo to hidden floors, strange puzzles, and unexpected alliances.

Edgar, an eleven-year-old orphan, finds a book that reveals significant secrets about Atherton, the strictly divided world on which he lives, even as geological changes threaten to shift the power structure that allows an elite few to live off the labor of others.