Saul visits Carrie, who has dipped into a deep depression in the aftermath of her recent manic episode. He learns that she's obsessed with the case because she's in love with Brody.
Against Estes' advice, the vice president continues to go through with his plan to announce his presidential candidacy during his speech outdoors. The police organize checkpoints around the area, but Walker manages to slip in by hiding in the backseat of a woman's car. When the woman arrives home, he grabs her and ties her up. Then he sets up to shoot the vice president from her window.
Brody leads grace at his last meal with his family then goes out to the garage to pray to Allah. His daughter, Dana, catches him and he reveals he has secretly converted to Islam. She agrees to keep it between the two of them, but she seems to sense something is off about her father.
As Carrie's medication begins to set in, she tells Virgil to take her to the area where the vice president is going to make his speech. He tells her it isn't her job anymore, but she insists and convinces him that there might be some truth to her theories.
Saul, who has been investigating Carrie's suspicions all along, tries to get some information out of Estes, about the redacted document that suggests a drone attacked Abu Nazir. Estes doesn't want to discuss it with Saul, and it seem like he knows something he doesn't want to tell Saul.
Worried, Dana asks her father to not go to the vice president's event, and he tells her not to worry, she's safe. She says she's more worried about him, but he insists he has to go. Off he goes with his explosive vest on.
As soon as the VIPs begin to show up at the event, Walker begins shooting. Security tries to protect them. Amid the chaos, Carrie asks Saul if she can be put on the response team. She has information that Brody and Walker are behind this attack. Saul order agents to keep her at bay, saying that she's unstable. This sudden turnabout raises the possibility that Saul is a mole working for Nazir.
Before the agents can get to Carrie, she races to Brody's house. She finds Dana and tells her what she suspects about Brody. Agents show up and take her away. But Dana calls her father and asks him if it's true, that he's a terrorist. The question upsets him, because he doesn't see himself that way, and actually decides to not go through with his plot.
Saul goes to the VP to demand the truth about the drone attack and uses incriminating documents showing the VP ordered the torture of terror suspects against him. The VP gives in and shows Saul a video of the order to attack Nazir with a drone, knowing many children will be killed in the process.
Walker wants to kill Brody for not going through with the plan, but Brody calls Nazir, who order Brody to kill Walker, and Brody shoots Walker before Walker can kill him.
Thinking she's crazy and deluded, Carrie goes to the hospital to get electric shock therapy. Just before she goes under she remembers Brody said the name "Isa" the night they spent together, and she realizes Isa is the name of Nazir's son. She says out loud with her sister by her side that she must not forget this. Then the shock treatment begins. Will she remember?