When a woman bursts into flames and explodes, Olivia and Peter start to look into it, and Olivia starts seeing things -- which Walter explains as possibly her seeing an alternate reality. The investigation leads back to the experiment Olivia was part of as a child, and points to a high member of the FBI as well as links to Massive Dynamic. Meanwhile Nina comes to Broyles with her concern that The Observer has been sighted again, and frequently.
In New York, a young woman in panic takes a bus to a hospital, but she cannot support the heat and leaves it. On the sidewalk, she has spontaneous combustion and blows up. The Fringe Division is assigned to investigate the case. Olivia sees two burned women instead of one and has weird visions, and Dr. Bishop explains that she might be seeing a parallel universe. Soon they find that the woman was a subject of a ZFT experiment and Olivia discovers through her abilities that she has a twin sister. When the Fringe Division tracks her down, the team discovers that she was abducted. Peter uses an invention of his own and they discover that the abductor called Harris by phone. Now the FBI is chasing Harris, who is the responsible for the crimes. Will the Fringe Division arrive on time to save the woman?
The Fringe team investigate a case of spontaneous human combustion. Olivia starts experiencing visions of the alternate Universe. She uses this ability to solve the case.
- Broyles (Lance Reddick) briefs the FBIers on the terrorist group ZFT. Their unpredictable acts are increasing in frequency.
A woman runs for the bus as Broyles continues his briefing, saying they recently learned William Bell may be behind the attacks. As the woman catches the bus toward the hospital, he tells the agents their goal now is to find evidence linking Bell and ZFT.
The woman has trouble breathing. She rings the bell to get off immediately. She stumbles around grasping her throat. She can't breathe. And then she bursts into flames.
Walter (John Noble) reads the ZFT manifesto -possibly his manifesto - and Peter (Joshua Jackson) asks what's up. Walter wants to show Peter something. He types the word "prophecy" on his busted typewriter and shows Peter about the offset key matching the manuscript. He says Bell wouldn't do these horrendous things. There are references throughout the manifesto about a chapter on ethics, but it has been removed. Walter thinks an original could still be in the lab. They get a call.
They check out the street flambe woman. Olivia (Anna Torv) says she'll call the coroner to transport the bodies. There's only one. Her vision shifts. She's seeing double but it goes away.
Nina Sharp (Blair Brown) of Massive Dynamic visits Broyles. She doesn't have her happy face on. She knows about the investigation. Broyles tells her they're investigating him for connection to biological attacks. Sharp says Bell isn't a terrorist. But he's unavailable to say so himself.
At the lab, Walter picks over the charred woman. He talks about people being full of energy at all times. Walter wants Peter to fire up the electron microscope, but Peter took it apart for a project.
Olivia visits Broyles. She thinks he moved his desk. Broyles asks about the other victim on the bus. But Olivia thought there was only one. Broyles shows her the crime scene photos -- two victims. Her vision shifts. Broyles walks in the door to his office and the conversation starts again. His desk is moved.
Sanford Harris (Michael Gaston) storms in, thundering about why they're looking into William Bell. He tells them to drop it. He leaves.
Before Olivia can ask if they're really going to drop it, Broyles tells her to get more evidence.
Walter cuts apart the charred woman. Astrid (Jasika Nicole) checks her dental records. Her use of the word "file" makes Walter wonder if he hid the ZFT manifesto somewhere. He wants his Geiger counter but Peter used it for his experiment too.
Astrid matches the victim: Susan Pratt (Jennifer Ferrin).
Charlie (Kirk Acevedo) and OIivia check out her apartment. She was a toll booth operator. They go through her things. Olivia finds a $30,000 check from an Isaac Winters. Charlie finds her bathroom, charred to the floor.
Peter returns from the grocery store, disappointing Walter by not finding him Frankenberry cereal.
Olivia tells the Bishops about the evidence of fires in Pratt's apartment. Walter thinks it's pyrokenesis, a word made up by Stephen King for "FireStarter", movie Drew Barrymore. But Walter thinks it's real. He says that a myth is just a unproven fact.
Walter thinks her pyrokensis was a newfound ability she didn't know how to control, either blow herself up or blow other people up. Stress would make her blow.
Charlie calls with an address for Isaac Winters in Charlestown.
Charlie and Olivia pay him a visit. He's an attorney. No one answers. Olivia busts out her lock pick tools. Inside they listen to a message from Pratt saying something "odd" happened. She calls again, increasingly agitated, asking what's happening to her.
Olivia goes out on the street and sees buildings burning and the sky black with smoke. Charlie comes out behind her, her visit shifts and all goes back to normal.
The Bishops check Olivia out at the lab. Walter wants to make sure she isn't on hallucinogens. Walter assures her she's not losing her mind because if she was, she wouldn't be concerned. She tells them what she's seen. Walter suggests it might be deja vu.
Walter shows her about the various possibilities for each daily reality. Deja vu is a glimpse of the other possibilities in other realities, the road not taken. This is actually a real theory in Quantum Physics called the 'Many World theory'. Each choice made splitters our reality creating another. But he doesn't know why she's seeing them. Olivia asks about Bell's drug trials of Cortexaphan.
Walter doesn't know, but he thinks there are reasons for her visions.
Astrid shows them another victim, discovered by a web site.
Malden, Mass. Peter and Olivia visit Emmanuel Grayson (played by Clint Howard who once appeared as Balok in the The Corbomite Maneuver (1966) episode). He runs a web site called galaxytruth. He starts to blow Olivia off as a Fed. Peter interrupts, saying he's not a cop and he needs to know what happened. He says the dead man was an exchange student. He asks if they're familiar with (to be played by Star Trek (1966) alumni Leonard Nimoy in up coming episodes) and Massive Dynamic. He says it's a cover and the dead man is one of his test subjects. He thinks Bell is trying to activate his subjects. Some can handle it, some can't. He's creating super soldiers. And then he uses the word Khan. As in "wrath of." And then Romulans. About how Romulans have traveled back in time to change the present. (which happens to be the plot for the new Star Trek movie directed by JJ Abrams). And there goes his credibility. Peter says goodbye with the Vulcan "Live long and prosper." (In a shocking coincidence, as Jean Luc-Picard would say, "in for a penny, in for a pound"] creator J.J. Abrams' movie "Star Trek (2009)" is opening this weekend, featuring a cameo by Leonard Nimoy -- and yes, WE have..., NO shame! And yes, old guys do watch FRINGE!)
Nina Sharp puts the prime minister on hold to take an urgent call in which she tells someone not to do something. Then she takes another call. Then she tell's her driver to take her to the helicopter. Then she tell's the Prime Minister something has come up, good-bye for now! The Prime Minister says good-bye to her, too!
Back at HQ, Olivia wonders if maybe Grayson was right about the non-Vulcan parts of his story. Harris comes in giving Olivia her new assignment. He tells her to get a psych exam. She tells him she won't let him undermine her ability to do her job. He says it's a direct order.
A phone rings near her. Her vision shifts. The phone changes colors. She looks around warily as things move in slo mo. She asks Charlie about the Pratt case. He says the have half of Boston under lock down and asks why she's worried about a pair of charred twins. She shifts back to the present.
She runs a search on Susan's twin. They find Nancy Lewis (Jennifer Ferrin), her twin who went missing nine years ago. Nancy lives in Boston.
Olivia goes there. But Isaac Winters gets there first.
Olivia shows up with Peter. The door is unlocked. The apartment is in disarray. The window glass has been melted. Peter has an idea.
The forensic techs are on scene. Peter paws the window before they can print it. He cuts a circle out of the glass. Walter shows up. Astrid shows up with whatever Peter has been working on.
He says they're going to find out who kidnapped Nancy.
Peter sets up his giant tube looking machine. He made it for Walter so he could reconstruct his water damaged records. It restores audio. He uses an electronic microscope to take a high resolution image of whatever, then a computer translates. He thinks the heat the twin generated when she was stressed and kidnapped would have left microscopic grooves on the glass.
He scans the glass. When he plays it the glass shatters. He slows it down. A low humming sound comes out. Then they can hear a woman screaming for help and a man talking.
They replay it. Olivia wants to hear the man dialing his phone. Her cell phone app can dial the number from the tones. It rings.
Agent Harris answers.
(after the break) Charlie answers his phone. He and Olivia watch Harris get into his SUV. They follow him. He goes to a warehouse.
They bust off the padlock and go inside.
Harris approaches a bunch of computers in a monitoring room. Isaac Winters is working on Nancy, strapped to a gurney. Harris tells Isaac "he" is losing patience and they need "it" done.
Olivia finds a room with pictures of Nancy and Susan and other cases they've investigated. And a picture of her. There's a shot in the other room behind her. A man shoots an agent and Olivia drops him. Olivia goes looking for Harris and finds Isaac. She shoots him.
Olivia runs in to help Nancy. As she tries to unstrap her from the table, Harris shuts the door behind her. Harris won't let Olivia out. If Nancy can't control her fire, she'll explode and solve two problems, Harris says. Nancy is heaving and overheated.
Harris calls someone and says they have an active.
Olivia tells Nancy what's happening and she can control it. She tells her to focus on anything. Nancy zeroes in on Harris on his phone in the other room. He starts to stagger. Nancy stares intently, calmly. And then Harris bursts into flames and keels over.
Olivia joins the Bishops in a diner. With Peter in the can, Olivia asks Walter: "What the hell did you people do to us?" She wants to know what he and William Bell did to them. Susan Pratt and Nancy Lewis are from Jacksonville, just like her.
He says they meant no harm. They were trying to prepare them to become capable. Something terrible is coming, but he doesn't know what. Through tears, he says he can't remember.
Peter comes back from the bathroom and Olivia is gone. He asks what happened as Walter holds Peter's hand.
Olivia gets in her car.
Nina Sharp rings Broyles' doorbell. She hands him a file. It's photos of The Observer (Michael Cerveris), all taken in the last 24 hours. She says he knows what happened the last time he appeared. They need to talk.
Walter listens to some old timey blues in the lab - his records working again. Thumbing through the box of albums he finds a manuscript. He flips through it, relieved. He thinks Astrid walks in behind him (but we can see it's a man in a suit) and he tells her he found the original manuscript with the extra pages. He reads: "Our children are our greatest resource. We must nurture them and protect them. We must prepare them so they can one day protect us."
He turns around. It's The Observer. "Hello Walter," he says, removing his hat. "It's time to go." "Is it time?" Walter says calmly. "I'll get my coat." The Observer walks out of the lab and Walter follows behind.
Nina walks into an apartment lobby. She takes the elevator. When she gets off she's greeted by two masked men. One is holding a gun with a silencer. He shoots her in the chest and she drops.