Former CIA agent Erica Shepherd, now known as one of the most notorious traitors in recent American history. Shepherd is brought out of a federal Supermax prison by FBI Agent Will Keaton to help stop some of the most dangerous acts of espionage threatening the United States today.

When a former CIA operative is murdered, Keaton enlists Shepherd to help recover valuable intel that could take down Tal once and for all. But the question remains, can Shepherd be trusted?

Following the discovery that a U.S. ambassador is selling classified intelligence to a Colombian cartel, Shepherd devises a plan to catch him that will push Keaton's moral code to the brink. Keaton brings a new member onto the team.

When intelligence obtained by Shepherd during her stint at the notorious ADMAX prison is linked to a pending attack on U.S. soil, Keaton and the CoIntel team embark on a manhunt to find and stop a deadly international operative.

Once Shepherd convinces Keaton that Anna Cruz is a mole inside the FBI working for Tal, Keaton decides to keep his enemies close. With a fox in their henhouse, Keaton and the team spy on one of their own, hoping Cruz will lead them to Tal.

After a bomb explodes in Jersey City, the Cointel team captures a key planner, Sam Fathi, who can lead them to Tal, the mastermind behind the bombing. When Sam proves difficult to break, Shepherd convinces Keaton to detain a former Egyptian intelligence officer to help, leading to an urgent mission to stop another bomb from going off.

When the FBI intercepts stolen NSA software intended for Tal, Keaton uses the technology as an opportunity to go on the offensive and sends Shepherd undercover. Keaton must choose between catching Tal or saving the life of an innocent teenager.

Flashbacks to the past reveal the fateful events that led CIA Deputy Director Erica Shepherd to betray her country and the ensuing investigation that put her on a collision course with Will Keaton.