Lorelei Aurelius is the smartest inquisitor in the mountain city of Ancris. When a mysterious tip leads her to a clandestine meeting between the Church and the hated Red Knives, she uncovers a plot that threatens not only her home but the empire itself.

The trail leads to Rylan Holbrooke, a notorious thief posing as a dragon singer. Lorelei soon discovers there's more to Rylan than meets the eye. He came to Ancris to solve the very same mystery she stumbled onto. Knowing his incarceration could lead to the Red Knives achieving their goals, Lorelei makes a fateful decision: she frees him.

Now branded as traitors, the two flee the city on dragonback. In the massive forest known as the Holt, they follow the trail of clues and discover something terrible. The Red Knives are planning to awaken a powerful demi-god in the holiest shrine in Ancris, and for some reason, the Church is willing to allow it. It forces their return to Ancris, where the unlikely allies must rally the very people who've vowed to capture them before it's too late.