Deacon's traumatic past comes into focus. Sharla pursues Joubert. Mae makes a terrifying discovery. After the location of the plot is uncovered, Bob considers his options and Joe compels Janice and Caleb to help him.

Joe's morality is put to the ultimate test as he attempts to stop the plague from being released.

Life changes forever when things do not go as Joe planned. Kat has to choose side.

With the task force closing in, Joe is forced to flee with Kathy. Marty suspects there may be a mole on her team. Reuel grows increasingly concerned about Bob's loyalty. Joe's search for answers leads him to two important people from his past.

CIA analyst Joe Turner finds a clue that sheds new light on a failed biological attack at a US football stadium. The evidence threatens Joe’s life along with everyone he cares about.

Joe continues piecing evidence together. Bob deploys a capture mission without Reuel's approval. Mae receives intel from Iris about Sam and Elden. Nathan confronts Gareth.

Joe is travelling in Europe when he is approached by a Russian agent, who says he can identify a mole within the CIA in exchange for protection. Joe begins to realise that escaping his old life may be impossible.

Reuel gets a nightly visit and realizes that he ended up in the middle of an unexpected conflict. Kat defies her own judgment when helping an old friend.

Tracy and Mae decide to disappear for a while. Joe has finally learned of Vasili's whereabouts and is aiming for a reunion.

Kat witnesses when Volk takes the law into his own hands. Mae's discussions with Senator Thrush have unintended consequences.

Joe continues to follow the evidence and makes a new discovery that intensifies his attempts to find Vasili.

Joe is lured back into the danger zone when he suspects that Bob's killer and mole may be the same person.