Detective Alex Cross is happy and content, planning his wedding to the woman he loves, Brianna Stone. But this blissful existence begins to unravel when Cross is called to the scene of the perfectly executed assassination of two of Washington D.C.'s most hated public figures: a corrupt congressman and an underhanded lobbyist. As more crooked politicians are picked off with similar long-range shots, public opinion is divided u is the marksman a vigilante or a hero? Media coverage of the case explodes, and the FBI assigns agent Max Siegel to the investigation. As Cross and Siegel battle over jurisdiction, the murders continue. It becomes clear that they are the work of a professional who has detailed knowledge of his victims' movements u information that only a Washington insider could possess. With the sniper, Siegel, and the wedding already to contend with, Alex receives a call from his deadliest adversary, Kyle Craig. The Mastermind is in D.C. and will not relent until he has eliminated Cross, and his family, for good.