The Americans is a period drama about the complex marriage of two KGB spies posing as Americans in suburban Washington D.C. shortly after Ronald Reagan is elected President. The arranged marriage of Philip and Elizabeth Jennings grows more passionate and genuine by the day, but is constantly tested by the escalation of the Cold War. Tensions heighten upon the arrival of a new neighbor, Stan Beeman, an FBI agent.
When Philip and Elizabeth are given an urgent task to plant a bug in Defense Secretary Caspar Weinberger's office, they risk exposure when an unwilling maid of the Weinberger home refuses to cooperate. Stan closes in on a member of the Soviet Rezidentura in an effort to uncover the identities of deep cover Directorate S operatives.
A crucial agent crumbles under emotional distress and threatens to topple a valuable network of KGB informants. Professionally, Philip and Elizabeth are tasked with infiltrating the FBI's new communications encryption system while personally they are forced to grapple with one of the darker aspects of life as a spy.
Elizabeth comes back from her injury and straight into what should have been a routine mission – but it goes awry, leaving her and Philip in fear not only for themselves but for their whole network… and family. Paige's suspicions have only grown in her mother's absence. Meanwhile, Stan continues to fall for the Russian agent who has started to play him.
Philip and Elizabeth complete their next mission - but not without complications - and Philip's fears about Elizabeth's readiness for action deepen. Stan tracks the KGB walk-in which leads to much praise at work and a deepening of his attachment to, and dependence on, Nina. Meanwhile, Paige snoops into her mother's family background and Oleg begins to scrutinize Nina's secret operation.
Just when Philip and Elizabeth think they have a quiet road ahead, an old friend returns to complicate things. Not only do they have to intercept a target who could prove valuable to the Soviet Union, but they also have to take on an important rogue mission without the support of the Centre. Divisions inside the Rezidentura deepen between Oleg and Arkady and there’s an upheaval at the FBI as the chickens come home to roost for Agent Gaad. Meanwhile, Martha’s frustrations threaten to blow Philip’s cover.
Philip and Elizabeth are finally assigned a new handler as Philip works to clean up the mess of the last operation and Elizabeth, in disguise as Clark's sister Jennifer, does her best to smooth things over with Martha. As Stan searches for a missing scientist, Oleg and Arkady continue to argue over how best to handle the situation on their side, leaving Nina once again caught between the FBI and KGB.
A dangerous Naval officer becomes the key to Philip and Elizabeth’s mission as well as a potential threat to their family's safety. Lucia, a Sandinista intelligence officer working with the Jennings, is tasked with getting Elizabeth access to Capitol Hill. Stan struggles with the potential costs of protecting Nina.