This book follows the events of Souls. Spoilers ahead.. Adia may have escaped the Shadow World, but she cannot escape the shadow. She fights for control over her body and sanity as she is kept in an insane asylum with a new startling ability.. Austin is held captive at Castle - a government facility run by someone who wishes to form an alliance with the shadows and uses his soul to gain information.. Dallas rescues former hunters being targeted by escaped dark souls. He meets an Eternal Guardian who has the ability to foresee futures. Together they build an army of hunters to fight in the impending Shadow War.