The Walking Dead Recap: Season 4, Episode 3 — ‘Isolation’

Sasha and Glenn got very, very sick, a herd attacked Daryl Dixon’s gang on the antibiotics run and the killer of Karen and David was revealed on the latest episode of “The Walking Dead” Season 4.

Here’s our blow-by-blow account of “The Walking Dead’s” episode 403:

Prison Graveyard: Glenn is digging a grave. He looks over at Patrick’s cross headstone, then, at Maggie. As the camera pans up, several of the residents are digging more graves as well. Things have gotten worse.

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Outside Cell Block A: Rick, Daryl and Carol are gathered around the still-smoking corpses of Karen and David. “You a cop?” Tyreese says to Rick. “You find out who did this and you bring ‘em to me.” Rick tries to get Tyreese to calm down, reminding him that this sort of reaction is no good, reminding him of a Season 3 scene where Tyreese saw Rick flip out (following the death of Lori). Daryl steps in to console Tyreese. The gesture backfires and Tyreese shoves Daryl up against a gate.

Stepping in, Rick bears the force of two of Tyreese’s punches before he turns the tables and pummels Tyreese into the ground. Daryl has to drag Rick off a bloodied Tyreese.

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Inside The Prison: Rick’s hand is sprained and going to need stitches. “I wouldn’t plan on typing much these next few days,” Hershel quips. As the two men chat, Hershel reveals they’ve lost 12 residents, “two killed in cold blood.”

Prison Graveyard: Tyreese is getting his emotions out by digging Karen and David’s graves. His eye is closed shut from his fisticuffs with Rick, but he won’t let Bob tend to him until the two are buried.

Outside The Canteen: Glenn and Hershel discuss the flu situation when Sasha walks out of a nearby cell block, coughing. Her lips are flesh colored. “I gotta see Dr. S.,” she says, looking at the two men, then away as she stumbles to Cell Block A.

Cell Block A: Sasha is getting worse by the second as she heads through the hall, looking for the doctor. In quarantine, one man is shaking, another woman coughing up blood. Still a third — too late, they’re a walker, locked in a cell. Finally Sasha finds Dr. S. He’s sick too. “We have to tell the others,” he says. “It’s starting.”

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Prison Library: Hershel informs the Council that everyone who survived the attack in Cell Block D is infected. Medicine has likely been cleared out of the hospitals, but Hershel thinks they might be able to find some at a veterinary college (which is 50 miles away). Michonne offers to go, but Hershel warns her off, telling her Daryl (who is leading the mission) has been exposed to the flu, she hasn’t. “He’s already given me fleas,” she quips. She’s going. Hershel suggests it’s time to separate the most vulnerable — the young — from the rest of the populace.

The Prison Fields: There’s a blockage to the water supply. Carol and Rick can’t get it pumping out more than a small trickle. “Is Carl pretty pissed about going into quarantine?” she asks Rick. The youngster is, but Rick notes it’s better to be safe. Seeing Tyreese on the hill, Carol suggests Rick should go talk to him.

Prison Graveyard: Rick and Tyreese come eye to eye. Rick apologizes. “It’s on both of us,” Tyreese says. Turning to the sad losses of Karen and David, Rick asks Tyreese if anyone had a problem with either of them, but Tyreese says they were well liked. Could the person who killed them have been trying to stop the spread of the flu, Rick wonders. “Now Sasha has it,” Tyreese says welling up. Things get tense again when Tyreese suggests Rick isn’t acting to solve the crime with a sense of urgency.

Carl’s Cell: Carl packs up his family photo — the one he went to retrieve in the bar in the “Clear” episode of Season 3 with Michonne. “I need you in there, keeping an eye on Judith, on everybody else, making sure they’re safe,” Rick tells his son before the youngster heads into quarantine. But, he also gives him a warning about the gun. Carl clearly isn’t fully trusted yet. Don’t fire unless “you absolutely need to,” Rick says.

Glenn’s Cell: Glenn knows he’s in bad shape. “Don’t come in,” he tells Maggie. “I have it.”

Prison Yard: Daryl tells Michonne he’s glad she’s there and not running off as they work on the car ahead of the run. “You know I’m not running off,” she says. Bob is also recruited, but they need a fourth.

Cell Block A: Tyreese is looking at the sick folks in the makeshift quarantine. Standing guard won’t be helpful if he, Michonne and Bob don’t make it back with medicine, Daryl tells Tyreese, trying to get him to join the run. He declines.

Prison Office: Hershel is making preparations to go on an herb/berry finding mission when he’s interrupted by a patrolling Carl Grimes, who tells the elder statesman he can’t let him leave the facility. “Let me?” Hershel asks. “I can’t stop you, but I have to tell my dad,” Carl replies (if he does tell dad that would be his third tattle in three episodes). Hershel tells him to go right on ahead and begins to head out. Carl decides not to tell Rick, but accompany Hershel instead.

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Cell Block A: Carol is ushering folks into the quarantine. Lizzie, the older of the two girls who lost their dad last week, walks up. She’s sick too. Carol ushers her inside, and politely turns down the pre-teen’s request to tuck her in, suggesting Glenn, who is already in there, will do a great job.

The Woods: Noticing Carl’s gun, Hershel asks the young man when his dad gave it back. He then begins to compliment the boy, telling him he’s grown. “There’s a responsibility about you. I think it’s done you good to step back,” he says. The quiet in the woods is interrupted by the sounds of a rotting walker against a tree. Another walks toward them, but they get out alive and head back to the prison.

Cell Block A, Execution Room: “Positive vibes,” Tyreese tells his sister, Sasha, who is on the other side of the glass in an actual former execution room. “Daryl’s got a group going out. They’re getting medicine,” he tells his sister. Realizing they could be back tomorrow, Sasha’s face lights up. “We got a chance,” she says. They share emotions through the window and Tyreese leaves.

Prison Gate: “Still got room for one more?” Tyreese asks Daryl. “Hell yeah,” Daryl replies.

Canteen Water Station: Despite Carol’s struggles, the water still won’t flow. She’s startled as Tyreese pops up with a request. “I’m going on the run with Daryl, but I was wondering, I know there’s a lot of people in trouble, sick. It’s just, I know how you are. You care,” he says, asking if she’ll look after his sister. She agrees. Before he leaves, she looks at him with a kindness. “What happened to Karen, I’m so sorry,” she says. He thanks her without words and walks away. Emotions getting to her, Carol tosses the water bucket. She starts to cry and knocks over one of the water barrels.

Outside Cell Block A: Rick is examining the evidence left where Karen and David died. He sees a bloody handprint on the door and holds his hand up for comparison.

The Stream Outside The Prison Fence: On her own, Carol tries to fix the water hose at the bridge, but she’s making too much noise and the walkers hear the commotion. Seeing what’s going on, Rick starts sprinting. “Carol! Run,” he yells. Carol takes out a walker, and as Rick finally gets outside the fence, he takes out another. “Piece of cake,” she says sarcastically after they’re safely back behind the fence, the water pipe still not fixed.

The Road: He’s still not referred to as The Governor, but as they make small talk in the car, Daryl says he would have helped track him down, but the trail went cold. Michonne seems less than impressed. Changing the subject, Daryl asks Michonne to hand him a CD as he fiddles with the radio buttons. Voices! In between the static they heard voices on the dial! Distracted by the revelation, Daryl plows into a walker, then another one. Trapped on a pile of rotting zombies, a herd surrounds the car. They have to run for it. “Stop for nothing,” Daryl screams.

Daryl pops out of the sun roof taking down walkers with his crossbow. Michonne does the same with her katana. Bob follows with a shotgun. But… where’s Tyreese!

The door’s ajar, but Tyreese is not moving. They shout to him. Finally he decides to see sense, but it’s too late. “Go on,” he tells them. He’s going to save them by taking on the endless herd on his own.

The Woods: After sprinting, Michonne, Daryl and Bob pause for a minute when they hear a noise. It’s more walkers. No! It’s Tyreese, who cuts the zombies down in front of him. He miraculously escaped the herd! “Come on,” Daryl says grabbing him. Together they run.

Cell Block A: Hershel, who has gone into quarantine to take care of the sick, pours Dr. S something hot. He puts a hand on Dr. S’s shoulder. “If you weren’t in here already, you’d be in here.” Upstairs, Hershel tends to Glenn. “After everything… I’ll just get taken out by a glorified cold,” Glenn shrugs. Hershel tells him not to think or say things like that.

The Outside Canteen: “That was a stupid thing you did,” Rick tells Carol of going outside the gates alone, to fix the water. She agrees. Rick says she does a lot for the group and for the kids. “You sacrifice a lot. Is there anything you wouldn’t do for the people here?” No, she tells him and starts to walk away. “Carol, did you kill Karen and David?” Rick asks. “Yes,” Carol says.

“The Walking Dead” airs Sunday nights at 9/8c on AMC.

— Jolie Lash