Eighteen years old, Caina Amalas is a novice nightfighter of the Ghosts, the spies and assassins of the Emperor of Nighmar. Skilled with stealth and disguise, Caina is the unseen agent of the Emperor, working to maintain the peace and order of the Empire. When a scholar uncovers an ancient relic from the Empire's distant past, he unwittingly unearths dangerous secrets. Secrets that might destroy the Empire and kill Caina...