Martin prepares Kate for a perilous mission in present-day Paris. Meanwhile, Gabi confronts intelligence agents in Prague; a vulnerability in Dmitry is discovered; and Alex is recruited for a distinguished position.

Kate goes missing in present-day Prague. Also, Martin makes a risky proposition; Gabi learns that Blazek may have dangerous ties to Tamir; Dmitry is threatened in 2001 Prague; and suspicions rise about Terrence.

Martin works for Tamir in present-day Prague. Meanwhile, Gabi confronts Blazek about his shadowy activity; Kate is held prisoner in the president's compound in Chechnya; and suspicions rise about Dmitry and Ilyana.

A threat on a summit is investigated by Martin and Nina, who search for Tamir's associate in present-day Prague. Elsewhere, two assassins spin a deadly plan into motion; Tamir's wife gives orders to Beslan; and Dmitry struggles to complete his mission.

Martin makes a deal with the Russians to rescue Kate. Gabi struggles to make a decision about her husband. In 2004, Dmitry asks one last favor of Terrance. In 1972, the last pieces of the puzzle to understanding Martin Odum's identity are revealed.