Juliana Crain makes a new acquaintance in the Neutral Zone - an Irish fixer named Wyatt - and soon finds herself on the run and seeking Tagomi's aid. The Japanese test an atomic bomb. Joe Blake is sent on a diplomatic mission to San Francisco. Kido hires a new sergeant. Nicole Dormer arrives in New York to head a new propaganda campaign. The Smiths struggle with the aftermath of Thomas' death.

Juliana recognizes that her and Tagomi's fates are intertwined. Tagomi and Admiral Inokuchi realize the Reich is imposing a covert oil embargo on the Pacific States. Reichsmarschall Rockwell and J. Edgar Hoover plot against John Smith. Helen starts therapy to cope with her grief over Thomas, and takes drastic action to protect her family. Kido and Tagomi clash over Juliana.

Juliana and Tagomi pursue the mysteries of the films and Juliana reunites with an old friend. Childan is anxious to return to San Francisco now that the reprisals have stopped, but a potential new romance makes Ed reluctant to leave. Kido receives intelligence that sets him on a new path. Smith finds himself celebrated by Nazi high society at a screening of Nicole's new film about Thomas.

As the Reichsführer continues to provoke the Japanese Pacific States, Juliana barely escapes a deadly situation and discovers a trove of Nazi secrets. John Smith tangles with his political adversary. The Nazis prepare for "Year Zero." Joe and Juliana come to a turning point in their relationship.

With Wyatt's aid, Juliana flees San Francisco with the stolen Nazi secrets. Childan can finally return home; Ed decides to stay in the Neutral Zone. Tagomi makes revelations to Kido that change Kido's perspective. John Smith's career takes a turn.

Juliana’s instincts about Helen are put to the ultimate test. As San Francisco evacuates, Kido goes in search of his son, only to find himself a captive. A letter arrives, forever changing Childan and Yukiko’s lives. The BCR receives an unexpected offer of help from the Yakuza. Abendsen condemns Smith with his final prediction.

Smith and Helen’s true loyalties are placed on trial by an old nemesis. The BCR struggles to maintain order across the JPS. Kido is forced to confront his atrocities. Bands of roving vigilantes threaten Childan and Yukiko.