In Manhattan, some sort of architectural design firm has a little power flicker as the result of a "micro-quake," which have apparently been happening frequently in New York, in advance of a macro-quake, which rattles the building. The lights go out, and Jim True-Frost of The Wire suddenly has a beam sprouting from his shoulder, and an extra half-arm, and three-to-four legs, depending on how far above the knee you consider the leg to start.

The Fringe team arrives on scene to find a building that looks rearranged on the outside. Inside, they find people fused together, fused with inanimate objects. Walter figures it's a "quantum tectonic event" — atoms fly apart, the go back together, not always the way they're supposed to.

They find Mr. Pratchitt (True-Frost), still alive, freaking out, and question him. He talks about the tremors that have been plaguing New York, but no one on the Fringe team has heard anything about that. Pratchitt keeps asking to see his wife, only it turns out he doesn't have one. Walter asks him questions to determine if he knows where he is. It's 2010, Obama is president, but on Sept. 11, the terrorists attacked the Pentagon and White House. Then Pratchitt dies, and they find a second Pratchitt head growing out of the torso. We're in two buildings, declares Walter: one is from an alternate universe.

Astrid goes through effects from the alternate-universe building: Richard Nixon on a silver dollar and a double-decker car, which triggers a memory for Walter, who thinks he knows what's going to happen. He remembers a prank that he and Belly pulled in which they zapped a car into another reality, and shortly thereafter, a car from the alternate universe was sent over, since the universe seeks balance. Which means that a building from this universe is going to be sucked over to the other side. Of course it does! Fortunately, Olivia being special and all, should be able to see the glimmering of the building that's going to disappear. She did it before: during the cortexiphan trials! Walter wants to go to Jacksonville to recreate the circumstances of the original experiment.

So they go back to the original testing centre, where Walter takes Olivia into a classroom and tells her that sixteen objects in the room are from the other side, which should shimmer for her. She looks around, but can't see anything unusual, so it's experiment time! Walter puts her on a cortexiphan drip, which he says will create an "obstacle," and overcoming it will raise her emotional state, and it was his and Belly's theory that perception is largely a function of emotion: how we feel affects how we see things.

Olivia, on the drugs, finds herself in a forest. There's someone else there, though, a little girl, which naturally turns out to be Olivia's scared young self. Olivia comes out of the drug hallucination, and gives Walter guff for doing this to little children.

And it's back to the classroom, but Olivia still can't see any glimmer. And Walter figures that it's a specific emotional response they need from Olivia: fear, like the fear she had when she was a little girl but is incapable of now that she's an ass-kicking FBI agent, but she's going to need to get scared if she's going to save the people about to disappear.

Massive Dynamic's on board to try to track the quakes, looking for a pattern. Olivia's freaked out that she can't see what she's supposed to see. So hey! Suddenly, she's scared! And she can see which building's going to be sucked into an alternate dimension. And they evacuate the building and everyone's saved.

And later, when Olivia comes by the Bishop house because she's going out for drinks with Peter, she sees him glimmering. Walter asks her to keep the secret. And it's going to be two months before we know anything else about what's going on....