The KGB and the FBI both race to track down a vital agent… everything is at stake.

A devastating flaw during a mission forces Philip, Elizabeth, William and Gabriel to confront the depths of their patriotism… and their mortality. In Russia, in striving to be a better person, has Nina put her life on the line?

The Jennings’s approach their breaking points as both Philip and Elizabeth must handle loyal agents. Will they make it through with their patriotism – and sanity – intact?

Martha must finally face the truth she has denied – and her life may never be the same. Plus, a chilling new development in William’s work forces the Jennings to face the realities of what a biological war would mean.

Elizabeth completes the last steps of a very personal operation… but at what cost?

Philip tries with increasing desperation to get rid of a sensitive and dangerous package as family tensions in the Jennings House reach a boiling point when Paige shares a secret of her own.

Paige copes with new burdens that come with her family’s secret as Philip and Elizabeth struggle to contain their cover without destroying their daughter.

When Paige’s long-ago indiscretion threatens to resurface and destroy the family, Philip and Elizabeth find themselves scrambling – and Paige finds herself reevaluating who her parents really are.

As Paige deals with last episode’s trauma, she sees her mother in a new light… and finds she has inherited some of her parents’ skills. Plus, has Oleg reached his breaking point with Stan?

Philip and Elizabeth are in a high-stakes race against the FBI to recover a hazardous package. Will they get there in time? And will Paige follow her parents into the family business?

Philip and Elizabeth deal with the fallout of all they’ve wrought. What will happen when the FBI finds out about Gene’s suicide? How will Pastor Tim deal with the revelation that they are Russian spies? And will they be able to handle a dangerous, new bioweapons assignment?

Philip must consider his life with Martha and make a crushing choice from which there is no coming back.

The Day After premieres, making the stakes - and terrible consequences - of the Cold War plain. Even with that in mind, will Elizabeth be able to complete the painful process of the "Patty" operation?