The entire squad race against the clock to uncover the clues and solve the puzzles scattered throughout the city by a serial killer, who is taunting them to find him and the next victims on his list.
Carrie and Saul have identified Tom Walker's contact in Washington DC, only to discover that he has diplomatic immunity. They must tread lightly, or risk triggering an international incident. Meanwhile, Brody has been approached to run for disgraced congressman Richard Johnson's seat in the House of Representatives.
Elizabeth and Philip come together to deal with a mission gone wrong, but struggle to reconcile their ideologies; Stan welcomes a Soviet defector to America; Nina acclimates to her new living arrangements.
Philip faces a moral dilemma while developing an asset; Philip and Elizabeth's friction escalates; Stan develops a theory, with serious repercussions for national security; Paige makes a surprising birthday wish.