When Damon Wessex, commander of England's Royal Black Guard retires, William, the King of England, sets forth a new approach to dealing with their enemies.

Just as skilled, just as fearsome and just as deadly as the king's personal assassin, there is one thing that sets them apart - their gender. Born in the shadows, her identity kept secret from the king's closest advisors, she carries out missions so sensitive that she simply does not exist.

NO MERCY is the story of the beautiful but deadly assassin, Serenah Salvatori. Her job is to dispose of individuals whom society deems to be a dark curse upon its people and she does so with brutal efficiency. However, when such a mission goes horribly wrong and she is captured, the king knows only one course of action. Given no name, other than an identifiable birthmark, he sends Damon on a treacherous assignment to infiltrate France's notorious Clairvaux Prison to free her before her relationship to the king is exposed and she is executed. After her successful rescue, she recuperates while still pondering the identity of her unforgettable rescuer.

Without the king's permission, Serenah embarks on a dangerous mission to England on behalf of a victim of a malicious crime lord who has penetrated London's underground. She attends a masquerade ball to lure him to his death, however, soon discovers her mission compromised. Undeterred, she wages a war against England's untouchable, high society while Damon is one-step behind her unraveling her closely guarded secrets and determined to protect her.