Over at Formerly Massive Dynamic, another access code earns the agents access to Walter's brain sample, stored in one of those areas where the lit-up circular shelves pop out all cool and futuristic. Walter misidentifies his own brain tissue as "monkey feces" and then continues to talk about monkey feces while Simon issues instructions to Etta -- a mixture of saline and polysorbate 80 to transfer the neural tissue -- and to Walter -- take these pills. "Diazepam, mostly. They'll put you in a deep sleep, for ten minutes that will quiet your brain to allow the process to occur faster." What we're going to do is put you to sleep, jam this tissue back in your brain and ten minutes later you'll be all better! Walter calls Simon a "clever boy," which makes Simon smile. Simon explains to Etta the pretend science that will make this work, while Walter talks about how he once ate brains, which was sweeter than you'd think, apparently. It would pretty much have to be, wouldn't it? Oh and also he loves LSD, and he's delighted at the prospect of the brain solution being injected into the base of his brain.
Then he suddenly gets very tired and practically passes out on his feet. Fortunately, Simon and Etta manage to wrangle him into a chair.
And now he's sleeping, with Etta and Simon sitting and waiting for him to wake up. Etta asks what happens if it doesn't work and Simon says it has to. Then -- because you don't get Henry Ian Cusick if you're not going to use him -- he gets to deliver a monologue about his freshman year at Stanford (suuure -- casually drop in that you went to Stanford, Simon), which is when "the Purge" happened. It was 2015 and the Observers were going from house to house and dragging people out into the street and killing them and he figured out that that's why his parents sent him so far away for school; they were part of the resistance and they sent him away to protect him. That was the night they were killed. "And that was the night I knew I wouldn't give up until the Observers had gone."
Etta looks about ready to bear his children at this point. She says he never told her that and he replies that he never told anyone that. Etta says she was only four the last time she saw her parents, WHOMEVER THEY MIGHT BE. She says she can't even picture their faces anymore. Her fingers find the thing she's got on a chain around her neck.