The Walking Dead’ season 4 brings to life its third episode of the new year with “Isolation,” as Rick works to keep the sick quarantined and investigate the murders of Karen and David, while Daryl mounts a supply run that runs into at least 7500 seriously dangerous obstacles.

Last week’s ‘The Walking Dead’ episode “Infected” saw the prison dealing with the threat of illness, as well as walkers both inside and out of the prison, forcing Rick to make a difficult decision, while Tyreese discovered a much more sinister threat lurking about, so what does the latest episode of season 4 bring?

Read on for your in-depth recap of everything you need to know about ‘The Walking Dead’ season 4, episode 3, “Isolation!”

While Glenn and the others dig graves and Dr. S pronounces another victim, Tyreese shows Rick, Daryl and Carol the bodies of Karen and David. Tyreese angrily demands that Rick find the culprit, becoming increasingly violent with Daryl before attacking Rick outright. Rick lands a few punches in return, forcing Daryl to pull him off, injuring Rick's hand. Hershel patches him up, assuring him that falling off the wagon isn’t the worst thing to happen.

Tyreese furiously digs graves, while Glenn and Hershel realize that Sasha has become the latest to catch the mysterious malady. Sasha isolates herself with the rapidly-deteriorating others (among them, Dr. S) while the council debates what to do next. Hershel proposes that Daryl, Michonne and others raid a veterinary office 50 miles away for antibiotics, while those at the prison will quarantine the most vulnerable.

Carol and Rick realize their water pump has become clogged again, arguing about the priority of going outside to fix it before Carol suggests Rick pay his respects to Tyreese. Rick approaches the man, quickly smoothing over their fight, though Tyreese worries that Rick isn’t working quickly enough to solve the murder. On his way back inside, Tyreese suspiciously eyes more Woodbury residents being relocated for their illness, while Maggie discovers that Glenn too has grown sick.

Daryl expresses his gratitude to Michonne for sticking around, though they reason they’ll need more bodies for the mission. Daryl finds Tyreese standing guard outside the isolation ward, but Daryl reminds him it won’t matter if they fail to return with the needed medicine. Elsewhere, in his own isolation, Hershel grows restless and prepares to head into the woods before Carl finds him and insists on coming along.

Carol continually herds the Woodbury survivors into the isolation ward, reluctantly ushering in young Lizzie as well, while Beth assures Maggie from the youth quarantine that they’ll all be fine. Outside in the woods, Hershel commends Carl for his handling of responsibility over the last few months before Carl spies a walker rotted and molded over into a tree. Another with its leg in a bear trap approaches, though Hershel points out that Carl needn’t take it down, and the two saunter off in relative peace.

Tyreese visits Sasha through the glass, and assures her he can get the needed medicine, while Daryl and the others load up the fastest car available. Carol pumps the remaining water, surprised by Tyreese’s appearance as he asks Carol to look in on Sasha while he’s gone. After Tyreese departs, Carol kicks over the mostly-empty jug of water, and sobs over the desolate situation. Maggie yells at a returning Hershel for risking his life to bring fever-reducing tea to the sick, but Hershel insists that he’s chosen a valuable reason to risk his life, one of the few remaining choices available to them.

Rick examines the scene of Karen’s murder, while Carol takes it on herself to clear the water pump outside the prison, the ambient walkers distracted by a bicycle contraption along the fence. The walkers steadily encroach, as Rick sees Carol’s danger from a distance and races to her rescue in the nick of time. Meanwhile, out on the road, Daryl fiddles with the car’s radio long enough not to notice the vehicle driving straight into the path of a massive herd. With the car trapped, Daryl, Michonne and Bob fight their way out toward the woods, but Tyreese hesitates. When Tyreese finally emerges, he begins swinging wildly at all the walkers, seemingly enveloped by the crowd. Daryl, Michonne and Bob continue racing through the woods, walkers nipping at their heels, until Tyreese finally emerges, bloodied, but apparently unharmed.

Back at the prison, Hershel brings tea to a sickly Dr. S before the man’s bloody cough negates the need for Hershel’s mask. Hershel also tends to Glenn, urging him to believe that they’ll get through this, after all they’ve done. Outside, Rick points out to Carol that she does so much for the group, she’d likely do anything necessary to protect them. Rick asks her flat-out if she killed Karen and David, which she confirms, before walking off.

OUR REVIEW:

Herds, Carol and bear traps, oh my! While we're still not entirely certain how effective or how sustained the mysterious flu disease can prove as a recurring threat, we were intrigued to see what "Isolation" did with a quieter, more character-driven hour, albeit one that still had some spectacular zombie visuals. As you'll see with our comic-comparison later tomorrow, much of the hour lent itself to developing Tyreese, whom we clearly see to have a large heart capable of taking him to some very dark places. His rage and animation against Rick provide the most illumination of his character we've seen thus far, though his hesitation in leaving the car later on seems a bit difficult to process.

And speaking of dark places, how about that Carol? Though we've seen some increasingly proactive and borderline shady behavior on her part, it speaks volumes to the character's evolution that Carol would be the one to take the initiative in killing Karen and David, hoping to end the threat of disease then and there. Seeing as the plan failed miserably, we're interested to see what other steps Carol might take to protect those closest to her, assuming Rick even allows her the chance after being burdened with the knowledge of her actions.

Still no sign of any major human threats to the group, especially now that Carol has been outed as the killer for reasonably altruistic reasons, though the walker herd out on the road made for some of the more impressive zombie visuals we've seen in a long time. The framing of the shot provided clear homage to the sheer size of the crowd as presented in the comics, though we'll have to wait another week to find out if the group has managed to successfully evade such a large-scale threat, or if Tyreese suffered any unseen wounds from his reckless charge.

Once again, character development seems to be the key in rehabilitating 'The Walking Dead,' though understandably fans might soon go restless as disease kills off the redshirts, and increasingly inventive walker presentations bide time until the Governor's inevitable return.

Well, what say you? Did you get your fill of thrilling zombie killing?  What did you think about tonight’s latest episode, “Isolation”? Check out all our other ‘Walking Dead’ season 4 coverage, and join us next week for another all-new episode recap of episode 4, “Indifference,” on AMC!

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