A shoulder-launched missile attack on a convoy of vehicles leaving the U.N. headquarters in New York kills several diplomats, including the American ambassador. Security footage reveals that the killer behind the attack is a disgraced former special forces operative, Mark Alperi. But before U.S. intelligence operatives can catch up with him, Alperi is already onto the next phase of his plan. With funding from the nearly shattered ISIS, Alperi plans an attack on the U.S. that will be more devastating than 9/11. When Intelligence uncovers Alperi's plot, though, it becomes a race against time.