Back in Deerfield, Sean is writhing and screaming about being cut. "There's three of us and one of him," he yells, and Bernadette needs help from an orderly named Charles who helps wrestle Sean into his bed while Bernadette prepares a sedative. Popcorn Man will never taste that popcorn. He's lying dead on the floor. And Sean has calmed completely down. "He's dead. It's over," he says, and Bernadette looks at Charles, presumably getting ready to tell him to pretend this never happened so she doesn't have to deal with all the paperwork.
After the opening credits, Olivia and Lincoln Lee are at the mental hospital, where they're doing that thing where an agent gets filled in on the details of a case like FIVE SECONDS before he's going to be helping to interview someone involved. She's explaining what a killing in New York has to do with a mental institution in Deerfield: "Apparently, a nurse here watched the news report this morning, and last night a patient with schizophrenia had recounted the entire crime in great detail as it was happening," she says, leaving Lincoln Lee to lament the lack of normal days at work in this job. But... I mean, since this is Fringe, isn't this a normal day? Try to acclimatize, Lee!
Meanwhile, Walter's already there, because he's Mr. Field Trip now, and Astrid managed to lose him but finds him talking to a patient -- a Mr. "Silbiger" -- and suggesting that he's the one who turned Timothy Leary onto the whole LSD thing. I'm going to assume that the emphasis place on learning Silbiger's name means it's a reference to something, but it's beyond my capabilities to suss out.
As Bernadette leads them down the hall to Sean Keenan, she tells them Sean's been a patient there for about three years, although she's sure he spent time in at least two other hospitals before coming here. Olivia's having a hard time paying attention though, because she keeps having flashbacks (which isn't quite right, because this didn't happen to her) of going to St. Clare's with Peter to meet with the heroically bearded and crazy Walter all those years ago.
Sean is a little perturbed at the idea that the voices in his head may be real, but Olivia's not willing to commit to that theory quite yet. She shows him a picture of the victim, but Sean says he's never seen him before. "But you know how he died," says Lincoln. Not a question. Sean tells him he didn't hurt the guy, and the agents do know that. He can't hear the voices now, though; they come and go, and -- in response to a question from Walter -- they never come from objects, like a tree or a wall. They're always from inside his head.