Welcome to Hell, all ye damned and demented. As a demon living in Hell, Blaze has heard these words every Arrival Day, when the sinful humes are sent from Judgment to be punished for their sins. But when she finally becomes old enough to herd the weak and pathetic-looking creatures into the Arrival Station where they will be branded and assigned to their eternal torment, a freak accident with a celestial being sends her down a path that will make her question everything she's ever believed.

Caught in a web of lies, accusations, and the threat of a punishment far worse than death, Blaze must clear her name by helping a strangely intriguing seraph named Visala return to the mountains of Judgment. The only way to get there is by crossing the Outer Circles of Hell, a barren desert filled with creatures and traps so dangerous, no demon has lasted more than a few hours after crossing into it. And the only one who actually claims to know anything about what waits there is Father, a tongueless old hume man, and Sparrow, the dangerous hume woman who translates his croaks and hoots.

Along with her two best friends, Onyx-a massive demon with glistening black muscles and curved horns-and Cinder, a flirtatious demon who can change the color of her skin and mane to match her mood, Blaze must face the dangers of the Outer Circles, explore her feelings for a being she's barely dared to look at her whole life, and unravel a mystery that threatens to destroy her world.