Dalia Arrowood is a Crystalline. A living weapon granted magical abilities through elven experimentation, feared and loathed by the humans of Belestara. For ten years, she has kept a promise to her sister: stay hidden and never use her powers. Living by this promise has allowed her to live a safe and relatively normal life. But safety has a way of feeling like a cage, and Dalia longs for more than just the simple and mundane.

When fate brings Glenn Cahill to her shores, Dalia makes the choice to break her promise. Using her magic to heal his wounds she not only exposes her identity as a Crystalline but breaks the bars of her cage forever. Now exposed to the world as an abomination, Dalia follows Glenn to join the elusive White Stags, a human resistance against the brutal elven regime.

Leaving the safety of Tidesend behind, a shadowy masked figure from Dalia's past haunts her as a fearsome band of elves called the Wolven Hunt chase her and Glenn. Wielding magic of their own, stolen from the hearts of other Crystalline, the Hunt serves as a stark reminder of why she made her promises in the first place. With the comforts of her cage left behind, Dalia must learn to navigate a world set to see her as either one of two things: a weapon to be used or a monster to be feared.