Recruited as a field operative in a totally secret and uncompromising new spy agency, former Navy SEAL Scot Harvath is summoned when a bombing in Rome kills a group of American college students. The evidence points to a dangerous colleague from Harvath's past and a plan for further attacks on an unimaginable scale.

Harvath is tasked with re-establishing contact with the man to lure him out of hiding and kill him on the spot. But what if it is the wrong man?

Simultaneously, a young woman is struck by a taxi in a hit-and-run incident in Chicago. With only two intoxicated witnesses and over five thousand cabs in the city, the Chicago Police have given up on their investigation. But when the family's attorney digs deeper, he will uncover a shocking connection to the bombing in Rome and the perpetrators' plans for America and Europe.

As the story rockets towards a stunning climax in London and Amsterdam, the plots intersect in a race to prevent one of the most audacious and unthinkable acts of war in the history of mankind.