Tech prodigy Eva is resigned to life in the Commonwealth, as long as she's behind a computer screen. To her horror, the Priests Choose her to train as a bellator, one of the Commonwealth's enforcers. She's eerily good at it. If only she weren't taunted at every turn by her deadly mentor, Ari, to whom she's bound by a blood oath. She's falling for the magnetic Ari, but in the Commonwealth, love is punishable by death.

Thrown into the life of a bellator, Eva is no longer a sheep of the Commonwealth, but a wolf, learning to patrol and kill. Her inexplicable strengths make her a top bellator, drawing unwanted attention. Meanwhile, as she and Ari train together, their antagonism becomes grudging respect. But the more time they spend together, the harder it is for Eva to resist the lure of his green eyes, his grace and power with a sword, and the charm beneath the sarcastic front he shows the world. Things take a treacherous turn when a heated night in the woods reveals a dangerous secret—Ari has loved Eva for years.

Their feelings put their lives at risk, but their love is too powerful to deny. Meanwhile, Eva's mysterious physical gifts heighten to a terrifying degree. Soon, Ari uncovers a secret that could take down the Commonwealth itself. Will Eva set aside her fears and fight for freedom with the boy she loves, knowing it might destroy them both?