Lydia Green never had reason to worry much before. She lived in a timeless Glen on the edge of the Valleylands with her mismatched family of fairies, philosophers, and two troublemakers known as the Zs. But now, at age eleven, her world is turned upside down when rumors reach Mulberry Glen about a mysterious Darkness that dwells in the forest Tenebrae. Lydia knows it is nothing to be trifled with, but, fiery and headstrong, the Zs have other ideas...