Philip and Elizabeth Jennings are deep-cover KGB spies living as an American couple in suburban Washington D.C. Their primary goal is to serve the Soviet Union, but they also struggle to maintain their cover and protect their children, Paige and Henry, from their dangerous reality. Philip wants to protect his family and find a way out of espionage, while Elizabeth is fiercely loyal to the Soviet cause.

The season's central conflict revolves around the Jennings' dangerous bioweapons assignment and the increasing threat of exposure. When Pastor Tim discovers their secret, the Jennings family faces the agonizing decision of how to silence him, leading to a tense confrontation. Meanwhile, their handler, Gabriel, becomes infected with the very virus they are tasked with handling. The season escalates as the FBI closes in on their operations, leading to Martha's forced departure to Russia and the shocking execution of Nina in Moscow.

The season culminates with a series of devastating events. The Jennings are forced to eliminate threats, including Lisa, and Agent Gaad is killed. The bioweapons plot reaches a critical point with William's agonizing death after he infects himself to prevent capture. Ultimately, Philip and Elizabeth are offered a return to Russia, but their family remains fractured by the secrets and violence they have endured.

Season 4 of The Americans covers episodes 1-13. Here's everything that happened:

Season 4, Episode 1: Glanders - Philip, haunted by a childhood memory of killing a bully, confesses to Martha about Gene's death, causing her distress. Philip and Elizabeth receive a new bioweapons assignment involving a deadly virus called Glanders. Paige confides in Pastor Tim about her parents. Stan confronts Philip about his relationship with Sandra. The episode concludes with Philip holding the vial of Glanders as Stan pushes him against the garage wall.

Season 4, Episode 2: Pastor Tim - Elizabeth discovers Paige confessed their identities to Pastor Tim, leading to a debate with Philip about whether to eliminate him. Philip smuggles the Glanders sample, killing a security guard in the process. Elizabeth learns of her mother's death. The episode concludes with Elizabeth acknowledging they are in trouble.

Season 4, Episode 3: Experimental Prototype City of Tomorrow - Philip and Elizabeth grapple with Pastor Tim knowing their secret, fearing the impact on Paige. Gabriel suggests eliminating Tim and his wife, setting up a family trip to EPCOT as a cover. Elizabeth cultivates a relationship with a Korean-American woman for unknown purposes. The episode concludes with Philip and Elizabeth learning Gabriel is infected with Glanders.

Season 4, Episode 4: Chloramphenicol - Philip, Elizabeth, William, and Gabriel quarantine after glanders exposure. Elizabeth calls off the hit on Pastor Tim. Martha dates Aderholt while Stan searches her apartment. Nina is executed in Russia. The Jennings family goes bowling.

Season 4, Episode 5: Clark's Place - Philip comforts a panicked Martha, providing her with a new contact number. Oleg learns of Nina's execution, deepening his disillusionment with the Soviet Union. Philip and Elizabeth attempt to manipulate Pastor Tim's perception with a fabricated story. The episode concludes with Philip and Elizabeth engaging in intense lovemaking, set to "Under Pressure".

Season 4, Episode 6: The Rat - Philip moves Martha to a safe house after realizing the FBI is closing in. He confesses he's KGB, shocking her. Stan and Aderholt inform Gaad that Martha is suspected of espionage. Martha, feeling trapped, flees the safe house after discovering Philip has left. Gabriel is unable to stop her.

Season 4, Episode 7: Travel Agents - The KGB and FBI race to locate Martha after she flees the safe house. Elizabeth finds her first, punching her to stop her from screaming, and returns her to the safe house. Philip reveals his real name to Martha and tells her she is being sent to Russia alone. Gaad realizes Martha is a traitor, understanding his career is likely over.

Season 4, Episode 8: The Magic of David Copperfield V: The Statue of Liberty Disappears - Martha departs for Russia, leaving Philip distraught. Elizabeth attends EST and clashes with Philip, leading to a major argument. Elizabeth kills Lisa when she threatens to expose their spy work. Gabriel grants Philip and Elizabeth a break from operations. The episode concludes with a time jump, showing the family seemingly at peace.

Season 4, Episode 9: The Day After - Elizabeth, as Patty, continues manipulating Young Hee's husband, Don, drugging him and staging a compromising situation. The Jennings family watches "The Day After," prompting Paige to express her fears about nuclear war. Elizabeth's actions destroy her friendship with Young Hee. Philip takes Paige for a drive in his Camaro to ease her stress. Elizabeth tells Philip, "I'm going to miss her".

Season 4, Episode 10: Munchkins - Pastor Tim's disappearance in Ethiopia prompts his wife to threaten the Jennings with a blackmail tape. Elizabeth continues her seduction of Young Hee's husband to gain access to Level 4. Agent Gaad is killed in Thailand by KGB agents. Paige tells her parents that Pastor Tim is safe and apologizes for not trusting them. Elizabeth considers Gabriel's offer of finding another way into Level 4.

Season 4, Episode 11: Dinner for Seven - Elizabeth completes her mission with Don, manipulating him by feigning pregnancy after drugging him. Philip, Gabriel, and another operative, posing as Patty's family, extract information from Don's office. Stan ends his relationship with Oleg. The Jennings host a tense dinner with Pastor Tim and Alice, interrupted by Stan's arrival. Afterwards, Elizabeth kills a man who threatens her and Paige, leaving Paige horrified.

Season 4, Episode 12: A Roy Rogers in Franconia - Paige grapples with the aftermath of witnessing Elizabeth's violent act. Oleg, concerned about the bioweapons program, tips off Stan about the Soviet spy within the US bioweapons lab. The FBI identifies William as the inside man. William has a crisis of conscience. The episode concludes with Elizabeth telling Paige that Philip is meeting a man with a weapon to defend Russia.

Season 4, Episode 13: Persona Non Grata - William, tailed by the FBI, infects himself with the Lassa virus to prevent capture, resulting in his agonizing death. Arkady is declared persona non grata and must leave the U.S.. Gabriel suggests Philip and Elizabeth return to Russia. Philip's son Mischa, having left a Soviet mental institution, seeks him out. The episode concludes with Philip forbidding Paige from seeing Matthew.