Aaron Roman Weiner

Martha and Clark's marriage meets its most challenging test yet; pressure on Philip intensifies; Elizabeth turns to Gabriel with a difficult request; Nina receives a new assignment that reconnects her with her past.

Philip and Elizabeth disagree over handling orders from the Centre; Philip enlists Annelise on a mission with an unexpected outcome; Stan tries a new approach to mending his marriage with Sandra amidst learning tough news about Nina.

Elizabeth disguises herself as Clark's sister in order to clear things up with Martha, while Philip attempts to clean up the mess leftover from their last operation.

Philip and Elizabeth both find themselves faced with painful turns in their various missions. Stan fights to gain access to an American military program that could give him the upper hand in his battle of wills with Oleg.

A shocking new development in William's work leads the Jennings to face the dangerous realities of a biological war.

Both the FBI and the KGB compete to try and find an important agent; the Jennings are forced to face the reality of what biological warfare would mean.