Enne Datchery and Muriel vas Veldina, ex-lovers and witches with a shared apprentice, are tasked by the Citadel to repair an old grimoire together, despite the fact their relationship is tense at best. The situation is further complicated when the book is stolen, and tracking down the thief stirs even more of Muriel's past. It swiftly becomes clear to the two that dealing with their fractured relationship is going to be the easy part of the assignment—if they can live long enough to complete it.