Eight years after being listed as missing in action and presumed dead in Iraq, Marine Corps Sgt. Nicholas Brody is found alive in an Al Qaeda prison. He returns home to a hero's welcome and begins reconnecting with his family. His wife Jessica welcomes him back while his daughter Dana has only a slim memory of him. Son Chris doesn't remember him at all. He's not aware that his wife had begun a serious relationship with his best friend. Meanwhile, CIA agent Carrie Mathison has been back in Washington for 10 months after a tour of duty in Iraq that ended when she bribed her way into an Iraqi prison to question a detainee minutes before his execution. In return for a promise to protect his family, he tells Carrie a great secret: a US soldier has been turned. She now suspects Brody and after the Agency dismisses her concerns, sets off on her own to find evidence against him.
Most that know her would consider CIA operative Carrie Mathison intense. As an intense person, she is not happy to be assigned to a desk job after the black mark incident ten months earlier while trying to obtain intelligence in Baghdad on a possible terrorist threat to the US, figuring out that threat at whatever cost being her primary focus. Back to present day, a CIA led mission on an Afghani safe house not only killed the thirteen hostiles in the house, but uncovered US Marine Sergeant Nicholas Brody, who had been MIA in the Middle East for eight years, alive as a captive in the house. He is considered a hero in the US, and the CIA wants to bask in the glory of this successful mission. However, Carrie, in part based on that intel from ten months earlier, believes that the enemies have turned Brody and he is that terrorist threat to the US. Without support from her CIA handler, Saul Berenson, who she considers her only true friend, or her section leader, David Estes, Carrie decides to conduct illegal surveillance on Brody upon his return home, which could land her and her associates in jail if caught. Her associates don't truly trust her, which is heightened by what they find in her house. Meanwhile, Brody returns home to a hero's welcome, but his transition back to his home life with his wife, Jessica, and his two children, Dana and Chris, the latter who doesn't really remember his father, is not without issue.
After being missing and presumed dead for eight years, Marine Sergeant Nicholas Brody is rescued in Iraq, and returns home to his family. But CIA agent Carrie Anderson suspects he might have been turned by his terrorist captors, and believes he could be part of a plan to attack America.
- CIA field agent Carrie Mathison is on the phone with deputy CIA director David Estes. She wants permission to speak with a prisoner she thinks has important intel. He's about to be executed and Carrie thinks is the perfect time to get information about the man he worked for, Abu Nazir. Estes says no, but she goes in anyway.
Carrie tells the prisoner she will take care of his family if he gives her the information. He whispers something into her ear as she is dragged away by guards.
TEN MONTHS LATER
Carrie returns home to her apartment early one morning. She has clearly been closely tracking this Abu Nazir for some time. She washes herself up, takes a blue pill of some sort and removes a wedding ring.
Carrie is late to Estes' briefing. He tells them about a Delta Force operation that resulted in the rescue of an American POW, Marine Corps Sniper/Scout Sergeant Nicholas Brody, who had been in captivity since 2003 and presumed dead. Brody said his sniper partner Corporal Thomas Wilson was killed in captivity. The room applauds but Carrie leaves with a concerned look on her face.
Carrie meets with Saul Bernson, who seems to be her boss and a mentor within the agency. She says tells him the prisoner she spoke with ten months ago said Abu Nazir had "turned an American POW." She didn't think much of it at the time because she wasn't aware there were any prisoners alive in Iraq or Afghanistan. Saul wonders why Brody wasn't just dropped off at a checkpoint. Carrie thinks Abu Nazir is playing the "long game." She's been in the "penalty box" and doesn't have as much access as she used to. He tells her to find a way to get him more intelligence.
Brody gets cleaned up and tells somebody he wants to speak with his family before his debrief.
Cut to a woman having sex with a guy with whom she seems to have an intimate relationship. The phone rings: "Jessica? It's me. Brody." A panicked Jessica stands up and tells the guy she has to leave.
Jessica returns home. She gathers son Chris and daughter Dana (who is clearly having some alienated teen issues) to tell them what has happened.
The family prepares for the reunion. Chris admits to Dana that he has no memory of his father. As soon as they leave the home two men in phone repair uniforms break into the home and begin setting up surveillance in every room. Carrie comes in to meet them -- Virgil and his brother Max - and gives them instructions to put video and audio surveillance devices in every room in Brody's home.
Brody is struggling on the flight to the ceremony, vomiting in the plane bathroom. It seems like Estes may end up getting the job of CIA director because of Brody's rescue.
Brody sees his family for the first time in eight years. It is awkward at first, but they embrace each other. The Vice President arrives and thanks Brody.
With Carrie watching closely on TV, Brody addresses the crowd. He gives a flawless performance.
Max finds one of Carrie's pills that she's been hiding in an aspirin bottle. Virgil isn't sure what it is.
On the way to the car the family is greeted by the man we saw in bed with Jessica earlier. His name is Mike and he's a Marine who is clearly close buddies with Brody.
The family returns home. There are hundreds of fans and members of the press waiting. They pose in front of a yellow ribbon tried around a tree in the yard.
Carrie convinces Saul to get her into Brody's next debrief. He makes her promise not to raise any eyebrows.
Carrie carefully watches the monitors. That night the phone rings but nobody is there. The reunited couple starts to be romantic and Jessica notices the scars all over Brody's torso. She cries. The couple has emotionless sex and Jessica weeps afterwards.
The debrief begins without incident. But when Carrie is allowed to question Brody she seems skeptical when he says Abu Nazir wasn't present during any of his interrogations. She doesn't believe him. We are shown Brody's flashbacks and he did meet with Abu Nazir during his captivity. The questioning gets borderline awkward.
Jessica and the kids are preparing for a welcome back party that night. Brody says he's still at the debrief, but we can see that he's in a car.
Virgil calls Carrie to tell him that Brody just lied to Jessica on the phone.
Estes tells Saul about Carrie making a scene at the debrief. Estes tells him the last time she was like this was when she got into the Iraqi prison and "nearly caused an international incident."
With Carrie and the surveillance guys in a van nearby, Brody meets with a woman. It turns out to be the wife of his USMC sniper/scout partner Thomas. She was the one who called and hung up because Jessica is upset with her for getting re-married. She asks how Mike died. Brody says he was beaten to death, but tells her he wasn't there when it happened. Based on a flashback it looks like he is lying again. Virgil asks Carrie about the pill they found. It turns out to be an antipsychotic and he is concerned. She says she has a mood disorder she's been dealing with she was 22 and nobody knows about it.
Carrie comes home to find Saul has found her surveillance setup. He tells her to get a lawyer because she's going to need to report her actions. She makes a halfhearted pass at Saul which is not well-received.
Carrie takes one of her pills and seems to be having a rough patch. She changes clothes, puts on her wedding ring and goes out.
At the barbecue Mike talks to Jessica. He mentions that they were close to moving in together and telling her kids about their relationship. He wants to know what happens next and she simply says "He's my husband, Mike."
Outside Brody notices Jessica and Mike together. He asks Chris about Mike helping out his mom while he was gone.
Carrie is at a bar where there's a jazz combo playing, with a guy she's clearly just met. She tells him she wears the wedding ring to weed out men looking for a relationship. Just before they leave together Carrie notices the fingers of the horn and bass players in the band. It reminds her of something Brody was doing.
Carrie excitedly visits Saul and shows him footage that during every public appearance Brody has been tapping his fingers in a pattern almost like a musical phrase. She thinks it's a signal to someone in the viewing audience. Saul is skeptical at first but eventually agrees she might be onto something. If it's a code of some kind, Saul thinks they should get the crypto guys on it. This seems to have bought Carrie some time.
Jessica wakes up to find Brody is gone. We see him out for a jog. While he jogs we look into his memory and see that he was the one who killed Thomas using his fists, and he did it with Abu Nazir looking on.
Brody stops running in front of the Capital building and stares at the dome.