In the next explosive novel in this New York Times bestselling series, Evan Smoak, having lived his life by the assassin's Ten Commandments, finds himself at odds with his oldest friend in the world, where principles are in conflict with honor, no rules hold-and no one may get out alive.

Evan Smoak was once a highly successful black ops assassin known as Orphan X, dedicated to a rigid set of operational rules. Even after going deep underground and remaking his life, Evan remains dedicated to his unbreakable code. But for the first time in his life, those principles have put him on a collision course with the man who might be his best friend in the world, Tommy Stojack.

Stojack, a gifted gunsmith who has created much of Evan's own weapons and combat gear, has apparently crossed one of Evan's sharply delineated lines. When Evan decides to have it out with Tommy, Evan is ambushed by a skilled crew of killers determined to take him down. But Evan is hard to kill and the dispute explodes into open warfare between Evan and Tommy. Now Evan has no choice but to track down and face his only friend.

In the meantime, Tommy has already left town in order to honor an old promise to a Navy friend who died in his arms. His mission is to help his dead friend's son. In a depressed rural area, with conflicts flaring up everywhere, that son could be responsible for the death of an innocent. And while Tommy is trying to keep him and his friends alive, Evan arrives with vengeance in mind.

But as deadly as the former Orphan X is, Evan isn't even the most dangerous threat to arrive on the scene.