In the final episode of the series, Hannah has received a phone call from a man claiming to be Derek's estranged father; an alcoholic who abandoned him when he was very young. Derek and his mother never spoke about him because it upset her too much, and Derek still finds it hard and says he doesn't want to meet him.
Meanwhile, a much-loved resident is in decline, which sets in motion a sequence of events culminating in the appearance of an unexpected visitor.
A mole hunt within the KGB causes suspicion amongst allies and shatters trust within the Jennings' marriage. Meanwhile, Stan's plan to keep his mole safe puts her at even greater risk of discovery.
The media introduces "Snowquester," Alabama calls the Voting Rights Act into question, Michael Bloomberg bans soda deliveries, and Wal-Mart inspires Brendan O'Connell.