Olivia brings up photos of the Observers and shows them to Broyles, and they wonder why they are contacting someone now even though they've know about them for three years. Astrid ran blood samples of the wounded Observer and confirmed that he had antibodies for the Spanish Flu, meaning he's at least 90 years old. Olivia believes that the Observer was trying to warn her, not threaten her, and promises Broyles that she'll notify him if she meets the Observer again.
In Boston, a girl is on the street doing sketches when she suddenly winces and then starts sketching something different on a clean sheet of paper. Once she's done, she rips off the piece of paper, puts it in her backpack, and walks over to a man in a suit, Robert Englehart. She hands him the paper and walks away, and the man admits to his friend that he doesn't know the girl. As they walk, a girder breaks loose and impales him, and the woman looks at the sketch... which shows him impaled by a girder.
At the lab, Peter and Walter go over the blueprints for the Machine. Olivia arrives and they explain they're trying to work out a way to get Peter home. She's happy that they're finally working together. As Walter goes to the restroom, Lincoln calls Olivia to tell her about Englehart's death and how someone predicted it. She thinks it was the Observer, but Lincoln tells her that a witness identified the artist as a teenage girl and that they can identify her.
The girl, Emily, arrives home and her father Jim, mother Diane, and brother Danny greet her. Jim says that his new job starts tomorrow. Later, Emily is in her room drawing when she gets another vision. Jim comes up behind her and comments that she's doing a sketch of the view from their lake house. She asks if he's tired of moving them around so much because of her, and Jim assures her that what matters is that they're together. Emily asks why God made her the way she is, and Jim says that he believes God has a purpose for everyone even if they can't understand it. He assures Emily that his purpose is to take care of them and says that at least it hasn't happened for a while. Jim closes the curtains and leaves.
In Boston the next day, Olivia is at her desk reviewing the sketch. Broyles comes over and notices that she is distracted by a headache. Olivia tells him that Lincoln is with the witness, but Broyles tells her that she received a call from health services that she's been there three times in the last month. She says that she has migraines and needed a prescription, and then asks Broyles if he believes in fate. When he admits that he doesn't, Olivia says that she didn't either until she ended up investigating a case where a victim's death is predicted. She wonders if the Observer does know something. Broyles suggests that they be extra careful about keeping her out of harm's way.
As Olivia takes pills for the migraine, Lincoln arrives to tell her that they have confirmed that Emily goes to school nearby.
As Emily is taking the bus to school, she gets a vision and starts sketching a man on the bus. She rips off the piece of paper and looks for him, but discovers that he's already got off. Emily stops the bus and goes after him, but loses him in the crowd. She then looks up at the sky and says that she tried.
Olivia and Lincoln go to Emily's home and talk to her parents. They have been going door-to-door with a photo of Emily and note that one of the neighbors says the girl lives nearby. The Mallums immediately deny knowing the girl, but once the agents leave, Olivia points out that there was a backpack in the apartment that matched the one on the girl in the photo. As they leave, they run into Emily as she comes home. Olivia asks about the sketch and Emily is sure that the man is dead. The teenager explains that she can sense death. Lincoln asks about her newest sketch but before she can answer, Jim comes out and says that they can't question his daughter. When Olivia points out that it's up to Emily, Emily reluctantly says that she doesn't want to answer the questions and go inside. Once she leaves, Jim notes that there are always people that want to study his daughter, like Massive Dynamic, and they never stop following Emily and look for an opportunity to abduct her for study. He asks them to let Emily have a normal childhood, and Olivia gives him her card. She offers to help if anyone harasses their family or if they want to talk further. As they go, Olivia asks Lincoln to run a background check on the Mallums while she meets with someone.
In the apartment, Jim tells Emily that she did the right thing and she can't put them at risk. Emily says that she saw something awful on the bus, but he says that nothing she can do will make a difference, and bad things happened to her the last time she tried.
Olivia goes to see Nina and asks if Massive Dynamic is still testing Emily. Nina says that they offered to help the family in return for testing, and that they know she's a precog. Olivia objects, insisting that it's abuse just like the abuse she suffered in the test program. They're interrupted when Emily calls to arrange a meeting with Olivia. When Olivia meets her at the park, Emily explains that it reminds her of a better time. She admits that Jim doesn't know that she called Olivia, and shows the agent the sketch of the man on the bus, dead and surrounded by dozens of other corpses.
At the lab, Walter examines Emily. She explains that she had her first vision when she was 11 and a man had a heart attack. The visions continued and her parents took her to a doctor, but people did tests and her friends got scared. The Mallums were forced to move, but the visions kept happening. Walter confirms that she has elevated theta-one waves. He says that he and Bell had a theory that some future events ripple backwards, and Emily's brain is sensitive to the ripples. Emily tells them that she can't control the ability, and that whatever she sees always happens. Peter wonders why she warns people if it won't change things, and Emily hopes that they can at least do one last good thing before they die.
Peter suggests that they ID the man in the sketch and Astrid checks bus pass photos. Meanwhile, Olivia thanks Emily for calling and asks her if she's sensing anything from Olivia. Emily concentrates and then looks scared. Before she can say anything, Lincoln brings Jim in. She asks her father to let the agents try. Pete and Astrid come up with the address of the man, Albert Duncan. As Lincoln and Olivia leave to find Duncan, Peter suggests that Walter hypnotize Emily to have her recall more of her vision. When Walter wonders how he can do that, Peter says that his Walter can do it.
Olivia and Lincoln arrive at Duncan's apartment and confirm that he works in construction and has been away all week. Meanwhile, Walter uses a machine to hypnotize Emily. She remembers being on the bus and then following Duncan as he left the bus. She then recalls seeing Duncan and the others dying in the middle of a building collapse. The girl hesitates and Peter has Jim reassure her, and Emily manages to reads part of a sign in Latin. Peter recognizes the phrase and calls to tell Olivia that the deaths will occur at a courthouse. Olivia has confirmed that Duncan was just divorced and lost custody of his children. Meanwhile, Emily tells Walter that she can see Duncan in the rubble, holding a radio. Peter figures that it's a detonator and that Duncan is setting up a bomb.
At the Allston Courthouse, Duncan goes through the metal detectors and on into the building.
The FBI arrives at the courthouse and starts a search, and they figure that the bomb is in the parking garage beneath the building, accounting for all the damage that Emily saw.
As Jim takes Emily home, she apologizes but he assures her that he's proud of her. However, he worries that they're in the system now. As they arrive home, Jim spots a black van across the street, just like the one they saw in Baltimore. He tells the family to start packing and ignores Emily's objections. However, she gets another vision and sees the park where she met Olivia earlier.
At the courthouse, Duncan asks for Judge O'Malley. Before he can find her, the authorities order an evacuation. Duncan figures that they're onto him.
Lincoln and Peter are with the FBI men in the parking garage, searching for explosives. They finally find Duncan's pickup truck, packed with explosives. Peter calls Broyles and warns that it's too elaborate to easily disarm. Broyles suggest that Olivia get outside of the blast radius, worried that the explosion is what the Observer was talking about. Olivia says that she won't live that way and continues looking for Duncan.
In the parking garage, Peter has the bomb squad expert determine the radio frequency that the bomb is set to, and then calls Broyles and tells him to have everyone tune their radio to the same signal.
Duncan finds Judge O'Malley and says that he's going to kill him. He triggers the radio detonator, but Olivia and Broyles arrive with the FBI and tell him that he's blocked the signal. Duncan opens his coat, revealing that he's wired himself with explosives, and insists that it's not his fault. Olivia tries to stop him, saying that nothing is written in stone and they don't have to die. She tells Duncan that he's the one in control, and that she doesn't think Duncan is ready to die. When Olivia tells her that the people around Duncan also have children, he breaks into tears and releases the detonator.
Olivia calls Jim, who doesn't answer. She tells him that Emily's vision helped saved hundreds of lives, and he goes to her bedroom. He discovers that she's gone and that the black van is no longer parked down the street.
When Jim calls Olivia, she confirms that the van was a dry-cleaning van. Olivia figures that Emily wasn't abducted and goes to the park with Lincoln. They find her sitting on a bench, chilled to the bone. As Lincoln calls an ambulance, Emily says that it's her time. In her drawing, her father is sitting next to her. Olivia says that her visions aren't inevitable and that they saved the people at the courthouse thanks to her. Jim arrives and Emily says that she's known for a while, but she didn't say anything because she knew he'd be there. Emily says that Jim was right and that everyone has a purpose, and her saving all of the people were hers. As Jim holds her, Emily dies quietly in his arms.
Later at the lab, Peter arrives and offers his condolences to Olivia. She confirms that Emily died of a stroke brought on by the excess electrical activity in her brain. Peter notices her photos of an Observer and explains that in his world, they show up at significant events throughout history. Olivia wonders if they know what will happen, and Peter explains that they don't predict the future, they simply experience it. He asks if one of them made contact with her but Olivia lies and says they haven't.
That night, Nina comes to see Olivia at her apartment and asks if she's all right. Nina apologizes for her earlier comments, and Olivia says that she thought she was going to die. She tells Nina that she's the closest thing she has to her mother. When Olivia complains about her migraines, Nina offers to make her some soup and says she'll send a new medicine that they've been working on. Meanwhile, the Observer watches from outside the apartment.