Over at Harvard, we flash from the frozen-in-amber student body of Earth-2 back over here, where Walter -- wearing headphones and brandishing a microphone -- is rummaging through a box of evidence from the Manhattan earthquake. The rest of the team has no idea in hell what he's looking for, so they start trying to figure out why the twenty-seven locations were selected. They've got a decidedly low-tech setup here; they're sticking pushpins in a folded-out paper map like some kind of goddamn animals. Peter figures it can't be random, and Olivia wonders if it's some kind of test.
Walter's ready to share his thoughts with the group and he takes his headphones off to disagree. He reminds them that everything here vibrates at 261 hertz -- or the key of C -- while everything over there vibrates at 392 Hz, the key of G. But everything in the box is vibrating at 329.6 Hz, which super-genius Peter doesn't need to be told is the key of E.
Walter has decided that the earthquakes are about Jones trying to tune both universes to the same frequency and so they're probably going to see a lot more of them, as Jones tries to break the barrier. And to illustrate when happens when a wall breaks, I guess, Walter has needlessly bought that Break The Ice kids' game where you hammer on the ice until it falls through or whatever. I'm glad he did that, because without it I'm not sure I would have understood the concept of something collapsing.
Flash over to the other universe, where Lincoln is hard at work at Fringe when another agent tells him he's got a visitor. And it's Nick Lane -- remember? One of the other Cortexiphan kids? Partly because his hair is a little bit longer than his previous buzz cut and partly because I have the memory of a goldfish, I remembered the name, but wondered for a while if this was the same actor. Anyway, he knows Lincoln because they grew up in the same neighborhood in Philadelphia. Lincoln doesn't remember him, I suppose because Nick was a couple of years behind him in school, but when Nick reminds Lincoln that he dated Nick's sister Kendra, the memory kicks in and he asks what he can do for him.
Nick apologizes for ambushing Lincoln, but says he didn't want to "call the hotline," and Lincoln's the only one he knows who works for the actual Fringe division -- but considering that all this civilian needed to do to get on the floor of this universe-life-and-death branch defense department was to say that he knows someone there, it doesn't appear to be that hard to get access.