She's cleaning up the city. One killer at a time.

To Tess Williams, murder is not a crime, it’s a vocation. A rogue assassin, Tess lives to protect the innocent and avenge the dead, so when a brutal slaying in suburbia grabs her attention, she wants just one thing – to nail the killer at any cost. But with no clues, no witnesses, and no evidence, how can she catch this cold-blooded monster?

Tess’s investigation plunges her into a perilous underworld filled with chop shop thugs, professional thieves, and mob bosses, where her survival relies as much on her wits as her fists. Yet no matter how hard she fights, she can’t uncover a single lead, only hints of a dark secret that lurks at the heart of the murder.

Battling on, Tess digs deeper, but then a shocking revelation stops her dead...

Her only chance of nailing the killer could lie in making a deal with the devil. But that would mean crossing a line. Becoming the very thing she's fighting against.

Tess is trapped in a deadly no-win situation as this simple case turns into her greatest challenge ever – can she sacrifice everything she believes in to bury the killer, or must she watch more innocent people die?