Ian, a young boy, witnesses the slaughter of his family and village at the hands of Horus, the Eternal Samurai. Horus, an undying, shapeshifting creature, has plagued the land for centuries. However, when Ian discovers a magical artifact that may be able to kill Horus for good, the hunt is on to find him and put him down once and for all. This book takes place in The Thaumaturge universe, ten thousand years after the first Thaumaturgical War, but that is not the main focus of the story.