Over to the interrogation, where Windmark, judging from Walter's spasming face, is picking Walter's brain, looking to find out who freed him and his team from the amber, and why.
Then, suddenly, he stops, surprised: "You're partitioned. Someone gave you information out of sequence. They did this on purpose -- to protect something," he says. The music swells, and Walter starts to shake even more violently, moaning and grunting in pain. A close-up of his eye makes me wince when a blood vessel bursts, coloring the sclera red.
After the commercial break -- with the dried brown stain on a nearby column a little less mysterious and a little more sinister now -- Windmark is turning up the heat on Walter, who's looking increasingly frantic. Windmark wants to know who taught him to fragment his thoughts: "Was it an Observer, as you call us, who partitioned you? No one else would know how to do that," he says. He orders Walter to put the ideas together. Walter resists -- he's turning purple and bleeding profusely from the nose with the effort -- and Windmark notes Walter's fighting much more than he would have thought possible, but Windmark is still able to piece together, from the whispers that we can hear, that it's a plan, possibly to defeat them.
"Walter Bishop, if only I had a unifier, I could unify these thoughts. I could go through the trouble to get one, but it would take weeks to break the biology key specific to your encryption," he says. I guess that's the Observer equivalent of when Briscoe and Logan explain to someone that they can get a warrant but that would take all day, so why not help them out?
Walter chuckles despite himself, but then Windmark leans in close, and laughing time is over! "That doesn't mean I will not get the information out. It will make it harder to get to it, but it will come out," he snarls. Walter's gripped in mental anguish again, and then we see flashes of a young Etta playing, blowing bubbles.