The Secrets of Underhill

Nick Sixsmith has spent her whole life on the road. The daughter of a traveling arborist, she moves from town to town with her mother, caring for the ironwood groves that people rely upon for survival. When a dangerous blight threatens these magical trees, the Sixsmiths must journey to the city of Mistwood for answers.
Nick can't wait to explore everything Mistwood has to offer: the bustling markets, the neighborhoods nestled behind a roaring waterfall, and the vast ancestral grove of ironwood trees. But dark secrets simmer beneath the surface as people start to disappear and tensions in the city reach a boiling point.
As the mystery grows, Nick and her new friends must follow the trail where it leads them—underground, to a strange and enchanting place called Underhill. Only there, among the roots of the ancestral grove, will Nick find a way to save the ironwood trees and the city she's come to love.