Ten-year-old Emma has battled dark creatures and protected her home from errant magic, but an unexpected letter brings her scariest trial yet―attending a wedding in Calebrin.

Da's younger sister has invited them for her ceremony, but Emma dreads the huge city, its strange people, uncomfortable fancy clothes, and worst of all: shoes. Her anxiety builds when Nan refuses to go, filling her head with worries about what could be wrong with her father's side of the family.

On Emma's first night in Calebrin, spectral crying wakes her. She creeps out of bed to discover a forlorn spirit wandering the halls, who seems to be trying to warn Emma of danger. Alas, Da's prim and proper mother has a low opinion of druids, and an even lower opinion of Mama. His younger brother takes particular delight in tormenting Emma, and her efforts to assist the spirit only annoy him more.

She suspects something far darker than an arrogant uncle lurks in the giant manor house where her father grew up. No longer afraid, Emma tries to help the ghost—before she becomes one herself.