Under the direction of new Chief of Staff BB Yates, Daniel Miller, Robert Kirsch, Valerie Edwards and the rest of Berlin Station embark on an unsanctioned operation to uncover a possible Far Right terrorist attack.

In a 24-hour episode set completely in Spain, Daniel uses Hector to further his mission with Otto, much to Hector's dismay.

Valerie works to obtain intel on the Far Right while Robert's teenage son Noah arrives in Berlin and asks questions. Meanwhile, Frost agrees to the Ambassador's request to spy on Berlin Station.

BB Yates's past is revealed while she juggles keeping Berlin Station's Far Right operation covert or revealing it to Ambassador Hanes; Daniel discovers a lack of trust between Otto Ganz and his daughter.

The Station's sting operation to catch the Far Right in an arms deal goes horribly awry, with Otto Ganz escaping. Meanwhile, Robert and Frost make plans to investigate the money trail behind the PfD's nefarious dealings.

Robert and Frost travel to Norway to investigate the illegal money trail leading to PfD; BB and Valerie devise a new plan involving a member of the Far Right; Daniel deals with the psychological consequences of his mission.

April weighs telling Robert about Hector's assassination plot; Daniel tries to arrange safe passage out of Berlin for Hector with help from Esther.

Hector is wanted by German authorities for the assassination of Katerina Gerhardt, but Berlin Station begins to discover there is more at play than a jaded ex-CIA officer.

Berlin Station continues to search for the truth behind Katerina Gerhardt's assassination and Nick Fischer's role in it, as a protest outside the US Embassy and calls to turn Hector over escalate.

CIA Officer Daniel Miller arrives in Berlin on a clandestine mission to unearth an anonymous whistleblower, alias Thomas Shaw, and reunites with his old friend Hector DeJean. As Daniel gets closer to Shaw, his quarry reacts in murderous fashion.

As Daniel pursues Shaw, Station Chief Steven Frost and his associates Valerie Edwards and Robert Kirsch gather intelligence on a Georgian Islamic radical in order to avoid an extraordinary rendition by Langley. By episode’s end, Hector surprises us all.

Frost and Kirsch worry their secrets will be unearthed when Langley investigators sweep Berlin Station to ferret out fodder for future Shaw leaks. Meanwhile, Daniel's hunt for the mole is put at risk.

Daniel and Hector embark on a dangerous operation to track down Shaw. Meanwhile, Valerie finds out the truth behind Iosava, and Frost and Kirsch deliberate future plans for themselves and the rest of Berlin Station.

Daniel teams up with Esther Krug of the BfV to prevent the next Shaw leak involving a foreign defector. Valerie and Robert spar over strategy as her investigation into Iosava gains traction; Hector gets a late-night visit from Shirley Pimple.

Valerie's investigation into Aleksandre and Ruth Iosava comes to a head in a German/American sting Operation involving Clare Itani, a CIA Officer and Hector’s lover. Langley's unannounced participation moves things from bad to worse.

Frost must pick up the pieces after the Iosava Operation goes sour while Robert explores a different angle. Hector goes rogue but brings Daniel with him, preempting a crucial moment of clarity.

Repercussions from the Iosava debacle leave Frost in the shadows and the Station in disarray as Robert embraces a new role. Hector finds himself in the hot seat, Valerie reveals a secret of her own––and Daniel inches closer to the truth.

The mystery of Shaw's true identity finally solved, Daniel confronts his own conscience as he learns the origins of "Thomas Shaw"; Valerie’s suspicions about Robert further escalate rising tensions between them, and Kelly Frost suddenly becomes an integral part of the team.

Daniel assembles the crew as they piece together the extent of Langley's involvement in the Iosava rendition. Steven and Kelly Frost reunite against the odds; Hector pursues a new approach for his atonement – and the Thomas Shaw mantle is passed.