A trip to Evanston, Illinois, is going to bring things a little more into focus, though. A woman comes home yelling for "Mark." No answer. She asks for help with the groceries. No answer. "John and Alice are coming over for dinner. Thought I'd make a roast." Hey, maybe he's dead because you BORED him to death. She heads upstairs. "Hey, Dow Jones, are you alive in there?" Spoiler alert! She walks into a home office, where Mark is slumped back in his chair. She goes to wake him, but unless she knows how to put all his brains back together again and back in his cranial cavity, Mark ain't waking up. She screams and screams.
Peter and Olivia stroll across the Harvard campus, with Peter shaking his head at how crazy the whole deal is, and how none of the people here have any idea. "If we do our job, they'll never have to," says Olivia, like that's supposed to make Peter feel any better. Charlie calls on Olivia's cell to tell them that the brain-snot thing has happened again, to a day trader outside Chicago. "When are you going to start calling them murders?" Olivia asks Charlie for some reason, and Charlie says, "When you find us a murderer." Olivia asks him to send her everything he's got on the victim.
They're about to head up the steps into the building when they notice an older woman staring at them. Peter says he'll meet Olivia inside, and walks over to talk to her, while Olivia slowly goes up, watching Peter.
"Are you Jessica Warren?" he asks the woman, who says she is. "I'm Peter Bishop," he says, and she says she knows. He tells her that he read her letter, and he understands why she wants to see his father. "But it's not the right time," he says, because his dad just got out of the institution. "After seventeen years--" he begins, and she interrupts him to snap, "And three months. I know how long it's been." "I'm sure you do," says Peter, not unkindly. He says he's very sorry, but nothing will bring her daughter back, not even talking to Walter. To be fair, if you were looking for someone to raise the dead, Walter's probably your guy. Jessica says she needs to talk to him. "To do what, to blame him for the accident?" says Peter. Jessica says it's between her and Walter, WHICH IT IS, PETER, but he says "It's not going to happen" and walks away.
Inside the lab, Astrid greets Olivia by saying that she's glad Ella's OK. The closed-captioning tells me that a toilet is flushing, which I can barely hear, but it does help explain why Walter comes out of a little room playing with his crotch. He excitedly tells Olivia that he's figured out what's going on. Something to do with a complex combination of "visual and subsonic aural stimuli" that amplify the electrical impulses of the brain, trapping it an endless loop. Olivia interrupts him because she doesn't understand, and Peter isn't there so Astrid pinch-hits and says it's like a computer virus that infects people.
Olivia's in her office shuffling some TPS reports when Peter comes in to ask a couple of rudimentary questions about the latest victim, but mainly so Olivia can tell him she knows who the woman was outside. Peter asks her what she thinks she knows. "That she's the mother of the lab assistant that was killed in a fire here almost twenty years ago." Yeah, that's pretty much it! Speaking of which, there isn't any fire damage in the lab. So I guess that means this fire did enough damage that it killed a woman, and Walter got sent to a mental hospital, and Harvard? I guess? Repaired the damage, replaced any destroyed equipment, returned the lab to the way Walter had it, and then shuttered it for the past seventeen years to wait for his return?
Anyway, Peter closes the door. Olivia says it's "none of her business." Little late to say that now, but Peter tells her to go ahead. "Does Walter know that she wants to see him?" asks Olivia, and Peter is all, "a-doy," and says Walter couldn't handle it. Olivia nods and says, "I see," totally not meaning it. He asks her if she thinks he could. "I don't know why, but I do," she tells him. He asks if she really thinks it's a good idea for the two of them to meet, and Olivia blathers on about how it's unresolved for the both of them, and that it must be hard for Jessica too, to come back to the place where she lost her daughter. Peter wants to know what her point is. "That you underestimate him, your father. And you shouldn't," she says. Peter gets up (Olivia throws her pen down in frustration) and walks out the door, passing Astrid, who can tell something's wrong but MANAGES NOT TO STICK HER NOSE IN.
Anyway, she's bringing in the information on the latest victim: Mark Rosenthal, 48, married. Olivia asks about next of kin, and Astrid says he just recently got married to a Miriam Dempsey. To make sure we all heard that, Olivia says, "Did you say 'Dempsey'?" Sure did! Olivia says she interviewed a Luke Dempsey this morning, and it turns out that Miriam is Luke's mother, making Mark Luke's stepfather.
Astrid suggests Luke's the killer, but Olivia dismisses that because Luke seemed "genuinely upset" that his friend was dead. Well, a good investigator like Olivia would know that A) that doesn't necessarily mean Luke's not the killer, and besides, B) Luke was acting weird, if anything, and maybe she should have picked up on the fact that Luke saying "we stayed friends" indicated their fathers didn't have the same relationship anymore.
Outside, Peter is actually ripping the phone off the wall as his father comes over to ask if everything's OK, because it sounded like he and Olivia were having an argument. Peter says it's no big deal, that he tried to expense a couple of Celtics tickets. Yeah, that TOTALLY EXPLAINS RIPPING A PHONE OFF THE WALL, but Walter accepts it because he's been there, man. He hopes Olivia doesn't notice the $2,000 worth of "baboon seminal fluid" he ordered, because he can't recall why he ordered it.
Olivia and Astrid come out of the office having settled on a suspect. Brian Dempsey, Luke's dad. He was fired by Greg's dad, and apparently threw a fit over it. And his wife recently remarried the Chicago day trader after a really nasty divorce from Brian. Peter asks about a connection to the car salesman. "Uh, we're still looking for that connection, but it looks like Dempsey's MO is to hurt people who screwed him over by going after their loved ones." Olivia calls Charlie, to tell him to get over to Brian Dempsey's house, because that's their guy.
The sun sets over Boston Federal Building, and Sanford Harass strolls into a room where the agents are looking through one-way glass at Luke Dempsey sitting in an interview room. Harass asks where the suspect is, and Olivia says there was no sign of the guy, so they picked Luke up at work. Harass asks for the plan. "We're waiting for the right moment," says Charlie, whatever that's supposed to mean, other than provoking an argument between Harass and Olivia. Harass figures they should just go in and "break him" and Olivia doesn't: "I think that Luke suspects there's something wrong with his father. If we go in heavy-handed, then he could shut down, or call a lawyer, and then he won't tell us anything." Harass tells her it's her job to make sure that doesn't happen, which is kind of what she's DOING, asshole. She snaps that she's "more than familiar with passive coercion," and Harass is all, "Good! Then put your little hands around his neck and squeeze. That's an order."
Harass leaves to go be a douchebag somewhere else, and Olivia and Charlie walk into the interview room. Olivia asks Luke where his father is, and Luke says he has no idea. She sits down and asks Luke to tell them about him, and Charlie figures Luke's dad has gotten a rough ride, what with being fired, dumped by Luke's mom. Charlie doesn't mention the baldness, but yeah. The baldness. "People don't under