Kate Wyler took the ambassadorship to London under protest and turned out to be extraordinary at it — brokering a peace between the US and UK that nobody thought possible. Her husband Hal is a former ambassador himself, brilliant, reckless, and constitutionally incapable of staying out of it. Now he's Vice President. What Kate learned at the end of last season about what Hal did, and who he did it with, is the kind of thing a marriage does not survive. Season 4 puts the two of them in the same house, on the same side of a catastrophe, and asks whether either the peace or the marriage can be held together.
