Olivia sits in a car at night in the rain, waiting for Anil to arrive. As she waits, she watches Loyalist workers take down resistance posters with Etta's name on them. Anil finally arrives and shows her a piece of Observer tech that they took from an Observer, still covered in blood. He says that it's the same one that Peter inserted into his own brain, and apologizes for not knowing what Peter was up to earlier. Anil then leaves for another resistance attack as Olivia contemplates the small piece of technology.
Peter is working at Etta's apartment, running Windmark's future on a plotting board. A few minutes later, Windmark and his assistant Observer teleport in. They find the plotting board and the assistant points out that Peter now has the ability to run futures. Windmark notes that the last point on board shows him entering the apartment at the precise moment that he looks at the board.
In the street below, Peter watches in satisfaction.
At the Harvard Lab, Astrid and Walter watch another of his Betamax tapes, telling them that they need to get an electromagnet from a junkyard in Fitchburg. Olivia comes in and tells them what Peter has done to himself, and asks Walter if he can neutralize the tech. He immediately prepares to run a diagnostic on the tech and tells Astrid to get him the brain from his porcupine man in cold storage so that he has an organic brain to test the Observer tech with.
Peter calls and Walter tells his son that he has to come back. However, Peter warns them that the Observers know about Etta's apartment and refuses to return, saying that they can't convince him to remove the tech. He insists that he's in control but Walter doesn't believe it and begs Peter to come back and keep his promise to stop him from slipping back to his old persona. Once Peter hangs up, Olivia says that she can't stand to stay in the lab and leaves on her own to retrieve the magnet.
Windmark is walking down the street and Peter is ahead of him, plotting futures. He sees Windmark cross the street and places a cup of coffee so that a man will spill it on Windmark as the Observer passes. The man immediately tries to wipe off the coffee with his shirt sleeve and Windmark dismisses him. He gets to the street and is forced to wait for the light to change, just as Peter foresee when he placed the coffee.
Olivia drives to the junkyard in Fitchburg and sees locals living there. One little girl, Darby follows Olivia at a distance as she approaches two men. She offers to barter with them and one man, Carlos, is startled when she says that she's there for a magnet. He tells her to wait there and goes to find someone while Olivia notices that there is a security camera monitoring the area. Meanwhile, Carlos gets the woman in charge, Simone, and tells her about Olivia. They bring up a hologram of Olivia and Simone realizes that it's the person they have been waiting for. She tells Carlos to send the men out and then goes out to see Olivia. Simone welcomes Olivia and tells her that they've been expecting her and have the magnet ready for transport.
Simone takes Olivia to the truck with the magnet and explains that twenty-one years ago, a man came there and talked to Simone's mother. He told her that he needed a magnet to save the world and asked Simone's mother to keep it safe until his representative came back. Simone's mother and then Simone herself kept the promise rather than sell the magnet for food, and Olivia has finally arrive to collect it. Simone says that she has some of her people getting the diesel fuel for the truck and says that she knows Olivia wants to wait until nightfall in any case to avoid the patrols. When Olivia asks how she knew that, Simone says that she has a minor clairvoyance gift and not only saw that, but saw the bullet that Olivia has in her pocket.
Astrid prepares the monitor and Walter tries to work out how to insert the Observer tech. It jumps out of his hand into the brain and they watch on the monitor as it alters the brain. It finally stops when it "senses" that the brain is unusable, and Astrid creates a computer projection. They confirm that the Observer tech causes the brain to form more convolutions, enhancing processing power, but overrides the areas of the brain controlling emotion.
While Olivia waits for nightfall, Darby approaches her and says that everyone knows about her. When Olivia wonders how, Darby tells her that Olivia is on the reward wire. Darby's father calls her away and Simone comes over with a glass of water. Olivia figures that it's trapped and the water is drugged, and draws her gun on her hostess. Simone drinks the water to show that it's harmless and realizes that Olivia has no faith. Olivia doesn't believe that she's safe and Simone invites her to leave and come back when the fuel arrives. When Olivia finally lowers her gun, Simone senses that Olivia has lost her daughter twice. As they talk, the men arrive with the fuel.
Peter watches Windmark on the street from a renovated office floor. Windmark teleports in just as Peter predicts that he'll arrive there. The Observer informs Peter that he realized that he was the one who planted the bio-bomb in the briefcase. Once they had a point to track Peter from, he made his own alterations to Peter's path so that he could direct him to that point in time and space. Peter and Windmark teleport and fight each other, fading in and out. Windmark gets the upper hand, slams Peter into a pillar, and feeds Etta's last thought into his mind. As he prepares to stab Peter with a knife, Windmark tells him that his emotions make him weak. Peter shoves him away and the Observer assistant teleports in. He manages to stab Peter in the shoulder before Peter teleports behind the assistant and stabs him. He then teleports away as Windmark closes in, and the Observer teleports down to the street. He's unable to detect Peter, who is walking away and favoring his wounded shoulder.
As Simone leads Olivia to the waiting truck, the woman says that there are mysteries in the universe and Olivia's presence there is evidence of that. She suggests that Olivia let her heart find her own intuitive way and insists that Etta is still with her. Olivia tells Simone that her clairvoyance is simply a gift, and that she has similar gifts. However in the end they mean nothing and that people assign meaning to such things make sense of them. Olivia says that everything is just numbers and that the Observers are simply better at them. As Olivia leaves in the truck, Simone tells her that she believes and that Olivia can't know anything.
Walter and Astrid heat the Observer piece with a air dryer, and they're surprised when Peter comes in. He asks Walter to suture his shoulder and Walter goes to work. As Walter sutures the injury, he tells his son about how the Observer tech alters the human mind and removes emotion. Peter already knows and tells his father that he should appreciate the experience of accessing the untapped portions of the human brain. Walter warns Peter that the changes will soon become permanent, but Peter insists that he needs the tech to be able to guide Windmark through a square at exactly 7:19 p.m., putting him back on the right path. When that happens, Etta will be avenged. Walter insists that he needs Peter and that they have to follow the plan on the tapes, but Peter says that he has to go.
As Olivia drives the train to Boston, she calls Anil and he sets up a warehouse to store the magnet. Continuing on, Olivia sees a car wreck blocking the road ahead. Two people are sprawled on the road, apparently unconscious. When Olivia moves up, she discovers that the female is a mannequin. The man, Briggs, draws a gun and orders her to surrender. His partner Stanton comes out of the woods and they demand her money. However, when they scan Olivia and discover that she's on the reward wire, they realize that she's much more valuable to them and knock her out when she tries to fight.
Briggs and Stanton take Olivia and the truck to their hideout in an old buildings. Briggs calls the reward wire and talks to an operator, asking for a meeting a truth church so he can't be scanned. When Briggs gives Olivia's name, the operator puts him on hold. Meanwhile, Olivia is locked up in the next room. When she recovers consciousness, she hops over to an old bandsaw.
A loyalist officer informs Windmark that an informer wants to turn in Olivia for the reward money and the Observer gives the go-ahead. The operator then tells Briggs to go to the truth church in an hour to make the exchange. As they finish talking, Olivia cuts off her ropes and checks an air tank to make sure that there is still some content.
As 7:19 approaches, Peter breaks into Observer headquarters and sabotages the elevator. When Windmark tries to go down in the elevator, nothing happens and he takes the stairs, just as Peter planned.
Olivia creates a fire to lure Briggs in and puts Etta's bullet in the air hose. When Briggs comes in, Olivia releases the pressure and the bullet shoots through Briggs' head, killing him instantly. When Stanton comes in, Olivia shoots him and then pries Etta's bullet out of the wall. She then calls Walter and tells him that she has the magnet and is on her way back to Boston. He tells her about Peter and Olivia looks contemplatively at Etta's bullet for a moment and then asks where Peter is going.
That night, Peter goes to a rooftop overlooking the square to watch Windmark as he approaches. Olivia finds him and Peter explains that once Windmark passes a fountain, he will be back on the course that Peter has charted. The next at 5:12, he will meet Windmark face-to-face and break his neck. To do that he needs to keep the Observer Tech. Olivia refuses to lose him and says that she's there because of her feelings for him. She tells her husband that he soon won't feel anything for her or for their daughter, and Peter explains that Windmark gave him Etta's last memory of the day in the park when she was with her parents just before the Observers came.
Olivia refuses to accept Peter's sacrifice and tells him that Etta is still with them as long as they have feelings for their daughter. Nothing the Observers can do will take away those emotions, which is their one advantage over the invaders. As Windmark approaches the square, Olivia begs Peter to hold onto Etta's memory and promises not to lose him again. Peter remembers Etta's memories of the park and looks at Olivia, who says that she loves her. After a moment, Peter takes out a knife and cuts the tech out of his brain. Olivia puts Etta's bullet in his hand and he collapses from shock as she tells him that she loves him.