And that does it: Astrid says he's stabilizing, and in the tunnel, the fungus has started to fall apart, so Olivia can finally drag a catatonic Lee out of harm's way. He comes to, coughing, and looks up at Olivia. "Hey, you look a little freaked out," he says. "You wanna talk about it?" he adds, and he's lucky Olivia didn't drop him on his head right there.
Back in the lab, everything is OK again. Walter's even offering the G.I. Joe to Aaron, who declines at first. "Toys are meant to be played with," says Walter, who adds that he's seen the movie with the talking toys, which he deems "oddly disturbing." I guess Aaron, who takes the toy, is just lucky Walter didn't talk about seeing the movie baked.
Anyway, Aaron's a little disappointed to learn that Walter isn't coming to the hospital with him, but Walter -- spying Peter in the glass in the fire extinguisher box -- says he has things he needs to do. "We'll see each other again soon, I promise," says Walter, right before Astrid wheels him out of the show forever.
Walter then solemnly takes a book from a shelf, and sits down, unwrapping a large metal hammer and spike, and we see the book open to a section on -- gulp -- pre-frontal lobotomy.
Cut to Olivia coming into the lab, calling for Walter because she heard about the good news with Aaron. There's no response, and she heads into the office, where we can hear a steady metallic tok sound, and here's hoping they just leave this to our imagination and NO OH MY GOD HE HAS A SPIKE IN HIS EYE and Olivia, thank god, keeps her shit together much better than I ever could, and takes the hammer from him, even while he's saying the area is completely numb and he knows what he's doing.
She sets the hammer down, picks up some gauze and slowly withdraws the spike. Jesus, it's heart-rending watching Walter break down as Olivia asks what he was thinking. "I don't want to be recommitted. I can't go back there. Please don't send me back," he says. Olivia doesn't know what he's talking about. Walter says he's going insane: "I've been having hallucinations. No matter what I do, they won't stop." Well, a great way to keep yourself from being committed is to give yourself a lobotomy! He's reluctant to tell her what the hallucinations are, but eventually he says he's been seeing a young man, his voice in Walter's head.
A dumbfounded Olivia pulls out a piece of paper with a sketch on it, which we can see now is Peter, and the sketch she had at the top of the show. "Does he look like this?" she asks quietly. Walter looks at it with his ONE EYE THAT DOESN'T HAVE A SPIKE IN IT, and asks where she got it. She drew it from memory, she says: "I've been seeing him in my dreams for the past three weeks."