Walter is having his monthly psych evaluation with a doctor from St. Claire’s. He admits to tinkering with his meds, but blames his recent “distraction” on his work. The agents watching over him have tattled about him covering up the reflective surfaces in the lab. Walter claims he’s running an experiment and blames his previous self-medication for his hallucinations. He sees Peter on the back of the doctor’s clipboard but lies that the “hallucinations” have stopped.
Somewhere in the woods, two bullies are chasing a smaller boy. He runs into some kind of underground access area. The bullies corner him but are stopped from pummeling him by some kind of growth slithering up their bodies. The bullied kid runs away.
After the credits, Olivia is doodling at her desk (hey, she has a desk!) while running face recognition software. She’s called Lincoln in to see how he’s dealing with all he’s learned about Fringe and the other universe. “I’m here,” she tells him, in an awkward attempt to be flirtatious and/or personable. Lincoln says he’s fine.
Then they get called to a tunnel in Hyde Park, where the bodies of two 12-year-old boys who’ve been reported missing just hours ago but look like they’ve been decomposing for months, have been found. A pissy Walter tells Broyles (via Astrid, although Broyles can hear him loud and clear over the headset) that he doesn’t know what’s causing the rapid decomp. Lincoln spots another set of small footprints leading in and out of the tunnel. There’s a witness somewhere out there… or another potential victim.
In the lab, Walter and Astrid catch a “remarkably pungent stench” coming from the body. Astrid goes to get scented candles. And maybe some face masks? No? Broyles stops by to check in on Walter; his doctor “voiced some concerns.” Agitated, Walter says he needs to examine the second body as well. He tries to explain why, but can’t concentrate as Peter’s started chattering at him. Bad timing, son. Walter breaks down in tears. “I’m not losing my mind!” he insists, then excuses himself.
Broyles gets a call from Olivia: they’ve tracked down the boy who classmates say the dead kids were planning to beat up. They corner ten-year old Aaron in the lunchroom, where he’s doodling. He’s still doodling when they bring him to the lab. Aaron is described by adults as quiet and friendless. His father is out of the picture, and Aaron has been staying with a neighbor while his mom works overseas.
Broyles has directed Olivia to retrieve the second body at the morgue, so she tells Aaron that Dr. Bishop is going to examine him. Aaron doesn’t like doctors, but Olivia assures him Walter isn’t at all scary. Then Walter comes stumbling in wearing a gore-covered apron and barks, “Take off your shirt and hop on the table.”
He quickly gentles his bedside manner, explaining that he’s taking blood “just this one time, I promise.” While he’s doing sciency things with the blood, Aaron picks up an action figure sitting on a shelf. Walter snatches it from him but then apologizes. He tells Aaron the toy belonged to his son, who died.
Astrid grabs Walter to show him how the candles keep blowing out near the body. Walter observes the body is pulling oxygen from the air, and is covered in more mold than before. Ew, ew, ew. Unbelievably, this episode (and this one) are the only times I’ve actually had to avert my eyes while watching this show. As Astrid and Walter watch, the body starts expanding. Luckily they’re able to get it into an incubation tank before it sprays a bunch of nasty spores.
Astrid calls to warn Olivia about the second body. The coroner doesn’t want to stop eating lunch to answer Olivia’s call, and by the time someone else gets to the phone it’s too late. Olivia and Lincoln arrive just as the body explodes. Lincoln moves to save the people inside the room but Olivia stops him. “They’re already dead,” she says.
After the break, a team in hazmat suits heads into the room, where some kind of black growth is covering everything. Walter tells the team they’re dealing with sentient fungi that paralyzes its victims to feed and grow. He assures them that it won’t “attack” as long as they don’t touch it. How the hell are they supposed to get samples, then? I’m assuming that’s on the agenda. Lincoln notices (as he is wont to do) that the fungus is making its way down the drain. Walter says it’s seeking water and nutrients. OMG, it’s headed for the water supply why is no one concerned?
Walter tells Broyles UV light or intense heat should kill the fungus. Broyles gets to ordering some. He’s sending Olivia and Lincoln with another team to destroy the fungus in the tunnel. Olivia awesomely requests flamethrowers instead of piddly-ass lights, but I’m sure if she found out fire was also Fauxlivia’s weapon of choice, she’d be Team UV in a heartbeat.
Walter has cleared Aaron, and tells him Astrid will take him home. Aaron says the neighbor who’s watching him doesn’t talk to him. Walter understands, as he has no family either. Aaron is surprised to learn that Walter lives in the lab. Walter says it’s better than the mental institution where he used to live. It’s a testament to how lonely this kid is that he still readily accepts Walter’s offer to stay for a while longer.
Walter says he won’t have time to entertain Aaron, but then we see them wearing tin foil hats and having milkshakes. Aw. Walter has told Aaron to call him by his first name. Aaron bluntly asks how Walter’s son died. Walter tells him the story, including the part about traveling to another universe. In this reality, the Observer didn’t intervene and Alt-Peter drowned in the icy lake. Aaron’s like, um, why aren’t you still in the hospital?
At the tunnel — where everyone is strolling about with no protective gear on — they’re waiting for the floodlights so they can see what they’re doing. By flashlight, Olivia sees chalk drawings like the ones in Aaron’s notebook. The floodlights come on —
— and back at the lab, Aaron starts complaining that “it’s too bright!” In the tunnel, the fungus starts expanding and knocking out lights. “Burn it all,” Olivia orders. Simultaneously, Aaron collapses with a fever. Walter calls Olivia to tell her whatever they’re doing in the tunnel is killing Aaron.
Walter and Astrid get Aaron into an ice bath, but his temperature only drops a few degrees. Olivia asks why Aaron wasn’t affected when Broyles’ team destroyed the fungus at the morgue. Walter can’t explain that yet. He doesn’t know how to break the bond between Aaron and the fungus (I can’t believe I just typed that) either.
Walter confronts Aaron, who’s resting, with his drawings. Aaron admits he’s been frequenting the tunnel because it makes him feel better. He thought it was just his imagination, but Walter realizes that the fungus wants to protect Aaron. He correctly guesses that Aaron led the bullies down there on purpose. Aaron tearfully swears he didn’t know what would happen. Walter comforts him and tells him, “You did nothing wrong.”
He calls Olivia and Lincoln in. His new theory is that they’re dealing not with “colonies,” but with a single organism that’s formed a psychic bond with Aaron. I don’t know why, but I’m thinking aliens. Walter posits that the organism is like a giant brain, one that he’s named Gus. Of course. Walter explains that the colony at the morgue hadn’t yet “connected to the network,” which is why it was heading down the drain, looking for Gus. Won’t someone think of the water supply?
According to Walter, Gus is becoming more developed (and more aware) as it grows. He thinks Gus glommed on to Aaron because of their “shared sense of isolation.” Aw, the sentient lethal fungus was just lonely, you guys.
Olivia gets a call from Broyles, who reports that Gus came up through grating six miles from the tunnel and killed a homeless man. Finally, somebody’s worried about the damn water supply. Walter needs more time to save Aaron. “You’re going to kill Peter!” he yells. “Aaron,” Olivia reminds him. Broyles gives him two hours to come up with a solution. Walter asks Astrid to set up a machine to chart Aaron’s brain activity, while Broyles decides to bring in “some help,” whatever that means.
At Hyde Park, Broyles briefs Olivia and Lincoln. They’ve got teams waiting throughout the city and have evacuated several buildings. Luckily, there haven’t been any more casualties yet. Lincoln asks Broyles how he plans to kill Gus. Broyles’s face is all, Gus? Seriously? Olivia explains that Walter named the fungus.
Broyles’s help arrives, in the form of a super-toxin from Massive Dynamic. Olivia calls Walter, who’s got Aaron in some kind of halo and is monitoring his vitals. He’s managed to isolate Gus’s brain wave, linked to Aaron’s prefrontal lobe. Since he can’t break the link, he’s seriously contemplating lobotomy. Olivia tries to buy more time, but Broyles relays news that the the fungus has reached a subway platform. Time’s up.
Olivia calls Walter with the bad news. In the tunnel, Olivia and Lincoln show the Massive Dynamic technician where to set up. Olivia reluctantly gives the go-ahead. The tech injects the toxin, which makes Aaron sit up in bed, screaming. It also makes Gus react, by attacking the tech.
Astrid informs Walter that Aaron’s lost consciousness and his blood pressure is dropping. “Do something,” she begs. I understand it’s a tense situation, but I don’t know what the hell she’s expecting Walter to do. At the park, Broyles orders Olivia and Lincoln to get out, just as one of Gus’s tendrils snares and paralyzes Lincoln.
In the lab, Walter miraculously realizes that the source of Aaron’s physical distress is the limbic system, or emotional center, of the brain. Broyles dispatches a medical team to Lincoln, although I don’t know what they could possibly do for him. Olivia tells Broyles that the toxin isn’t working for some reason. In the lab, Walter has determined that Aaron is holding onto Gus, rather than the other way around.
He injects Aaron with something to bring him around. Aaron doesn’t want to let go of the fungus because it’s his “friend” (this kid really needs to look into imaginary friends) and nobody else cares about him. Walter insists that he cares. “I can’t lose you,” he says. “Not again.” Astrid looks suitably concerned. Walter tells Aaron to trust that he won’t leave him alone. Aaron lets go of the fungus (I can’t believe I just typed that) and his vital signs start stabilizing. Astrid happily reports that the two brain waves have separated. In the tunnel, the fungus starts to die and Olivia is able to pull Lincoln from the organism’s grasp.
Astrid wheels Aaron in to say goodbye to Walter. Walter gives Aaron the action figure: he’s seen Toy Story and knows toys are meant to be played with. He also calls the movie(s) “oddly disturbing.” Heh. He tells Aaron he can’t come with him to the hospital, but promises they’ll see each other again soon. As he’s talking he spies Peter reflected in a glass fire extinguisher case.
Alone, Walter preps an awl and a mallet, and sets out a book with instructions on the procedure for a frontal lobotomy. I can’t see the title of the book, but I’m like 90 percent sure it doesn’t say anything about performing the operation on yourself. Poor Walter has got to be desperate.
Fortunately, Olivia arrives in time to grab the mallet and pull out the awl. She puts a cloth on Walter’s face to stanch the blood flow. “What the hell were you thinking?” she asks. Walter begs her not to let them send him back to St. Claire’s. “I’m going insane,” he moans. John Noble, as usual, is killing it.
He confesses he’s been having hallucinations for weeks. Olivia begs him to tell her about it. She shows him a picture she’s drawn of the man she’s been seeing in her dreams recently. Okay, honestly, it looks more like a composite created from the descriptions of about five different witnesses than Joshua Jackson, but it’s obviously supposed to be Peter. Walter is SO relieved.
“Who is he?” he asks, and Olivia has to admit that she doesn’t know, nor does her face recognition software. Walter says that because it’s a shared vision, the man they’ve been seeing must be real. “We have to find him,” he declares.