To Save Arrhinsal

Tolin lives on Arrhinsal, an island that floats in the sky two miles above the land below. One day, while hunting in the maze of tunnels that run through the island’s thick hedges, he encounters a girl who, her sword raised, has turned to face a huge hedgeboar. He urges her to run instead, and to escape with him into a tunnel too small for the boar to follow.

The girl, Brilley, is from the Castle—a high-walled fortress in the middle of Arrhinsal—where her mother is a mathematician and her father a librarian. Castlers call villagers like Tolin, who live outside the castle walls, Wilders. Tolin is suspicious of Castlers, but Brilley assures him that she has come into the hedge looking for someone like him.

Arrhinsal is in danger of falling from the sky. The island is held up by a natural magnetism but also by the magic of the Arrhinsal Tree, which is dying. Most everyone is fatalistic about the future, but Brilley has a plan. From old books, her father has discovered that, if