After his girlfriend mysteriously disappears from a cruise, Sean Walker discovers a conspiracy of global proportions.

President Martinez, furious about recent security failures, demands answers from Director of National Intelligence, Blake Sterling. When he doesn't receive the progress that he desires, Martinez decides to personally interrogate Michael Buchanan about his involvement in the assassination attempt. While Michael holds to his claim that he doesn't know who is involved, he inadvertently reveals incriminating evidence about someone deep inside the President's staff. Meanwhile, Dempsey dispatches Vicky on a new clandestine mission. And, elsewhere, Sean and Leila scramble to stay ahead of the covert ops that are trying to silence them and what they know.