A series of murders in New York City has stymied the police and FBI alike, and they suspect the culprit is a single killer sending an indecipherable message. But when the two federal agents assigned to the investigation are taken out, the FBI takes a more personal interest in the case.Special Agent Ty Grady is cocky, abrasive, and indisputably the best at what he does. But when he's paired with Special Agent Zane Garrett, it's hate at first sight. Garrett is the perfect image of an agent: serious, sober, and focused, which makes their partnership a classic cliche: total opposites, good cop-bad cop, the odd couple. They both know immediately that their partnership will pose more of an obstacle than the lack of evidence left by the murderer.Practically before their special assignment starts, the murderer strikes again – this time at them. Now on the run, Grady and Garrett have to figure out how to work together before they become two more notches in the murderer's knife.