The Walking Dead’ season 4 brings to life its second episode of the new year “Infected,” as the prison deals with the threat of infection, and walkers both inside and out of the prison, forcing Rick to make a difficult decision, while Tyreese discovers a much more sinister threat lurking about.

Last week’s ‘The Walking Dead’ premiere “30 Days Without an Accident” saw a supply run between the survivors and new Woodbury recruits quickly go amiss, while Rick attempted to help a mysterious stranger in the woods, and a survivor took ill under mysterious circumstances, 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 2, “Infected!”

Out by the prison fences, a mysterious figure attracts the walkers’ attention with a live rat fed through the fences. Meanwhile, inside, Tyreese and Karen separate for the night, and Karen just barely misses the zombified Patrick arising within the showers. Karen goes to sleep as Patrick fumbles his way into Cell Block D, haplessly chowing down on the neck of a sleeping survivor, rendering him unable to scream.

Rick and Carl get up to begin farming, as Glenn and Maggie similarly prepare for a shift change at the guard tower. Michonne rides off on her daily mission, as Carl asks his father for his gun back, before the sound of gunshots within the prison draw them all. Rick rushes inside, while Carl reopens the gate for Michonne to return, injuring her leg in the process of fighting off a walker.

Daryl, Glenn and the others fight off the walkers in the cell blocks, as Carol prepares to amputate a man’s arm, finding him to be bitten on the back of his neck as well, thereby beyond saving. When the fighting dies down, Daryl takes out the walker Patrick upstairs, as Rick reluctantly retrieves his knife to stop another from turning. Downstairs, the bitten man begs Carol to take care of his children after he’s gone, Lizzie and Mika.

Rick, Daryl, Hershel and Bob find another walker upstairs trapped within his cell, devoid of any bite marks and bleeding from the orifices like Patrick and a few other walkers. A Woodbury doctor suggests that both the man and Patrick likely died from an aggressive flu strain, one that could have spread to the pigs, and thrives in close quarter environments like the prison. Downstairs, Carol brings Lizzie and Mike to say goodbye to their father, though when Lizzie offers to stab her father’s brain before the turn, Carol is forced to step in for the terrified girl.

Outside the prison, Rick urges Carl, Michonne and Maggie to stay back for fear of the virus, while the council of Carol, Hershel, Daryl, Glenn and Sasha meet to discuss quarantining the sick. Tyreese and a coughing Karen pass by, for which the group brings them up to speed on the threat of illness, and Karen agrees to relocate to A block for the time being.

A while later, Carol finds Lizzie and Mika by the fence, and insists the girls will need to become strong enough to make quick choices in life or death situations. Daryl digs graves for the fallen, assuring Rick he’s earned the right to stay out of fighting and group decisions for all he’d done for the group, before Maggie alerts them to walkers collapsing a nearby section of fence. Inside the prison, Beth tends to Michonne’s wounds, as Michonne seems to recoil at the sound of Judith’s cries.

The group desperately attempts to kill walkers faster than they can pile up on the fence, as Sasha notices the dead rats someone must have been feeding them. Inside, Carol finds Carl building a cross for Patrick’s grave, and asks him not to tell his father about her training the other children with weapons, even if it makes him uncomfortable to lie to Rick. Beth pawns Judith off on a reluctant Michonne to clean spittle off her shirt, as Michonne begins to smile and weep from holding the baby.

Rick comes up with a solution to get the walkers off the fence, reluctantly driving outside the gate with Daryl, and releasing the sickly pigs one by one to lure the zombies away. Meanwhile, Carol makes peace with the girls, once again watching the walkers by the fence, as Lizzie agrees to keep a knife with her. A short while later, Rick dismantles the pig pen, as Carl confesses what Carol has been up to. Rick decides not to stop the weapons training, handing Carl back his gun as he straps on his own, and sets fire to the dismantled pen.

Finally, Tyreese goes to visit Karen in A-block with flowers, but quickly finds a blood trail to the yard outside, where Karen and another body have been burnt to death.

So, let's get one of the more obvious discussion point out of the way, namely that the Governor's absence from season 4, and showrunner Scott Gimple's more measured approach to drama have in only two episodes changed what we've come to expect from 'The Walking Dead,' here displaying a much quieter, more contemplative hour than the constant-looming tension of season 3. That isn't a complaint, mind you, 'The Walking Dead' has long-since needed a more dramatic spine to balance its constant kills and gross-out action sequences, but the changes won't necessarily go over too well for those looking for 'The Walking Dead' to unfold each with with a heavy hail of bullets.

Now that we've seen the old-world threat of disease crop up within the prison, as well as an apparent saboteur, we've got plenty of delivery methods to kill off the stream of redshirts, though relatively little investment in the inherent danger. So far the additions to the prison have served little beyond meat for the grinder, though the smaller moments of humanization afforded to Carol and her new wards do help to reinforce Tyreese's earlier words of the episode, namely that the fellow survivors in your immediate proximity become the only family you'll ever have. It's a small, belated point for 'The Walking Dead' to make in its fourth season, though we're clearly playing a bit of catchup in developing characters who offered little more than presence the previous year (cough, Michonne).

Of course, the hazy nature of the virus makes for a bit of difficulty investing in the threat, as we're not given to understand the nature of its spread, or the efficacy of exposure. Our guess would be that our mysterious saboteur could come to supplant the disease as a more tangible threat for this early run of episodes, given the absence of any real goal for the the group outside of basic survival. If not that ever-shifty Bob Stookey looking to weaken the prison's defenses, we'd place our money on that mysterious doctor we saw examining one of the bodies, who might have decided to take out Karen and the other body before the infection could spread.

If anything, "Infected" might only suffer from the current narrative's need to keep so many plates spinning at once, though we can appreciate the more soulful, contemplative approach to rehabilitating the series. Too easily we look back on season 3 for its stronger sense of pace and broader action, without remembering how scattershot things became in the back half of the season for lacking a strong emotional core.

Well, what say you? Did you get your fill of thrilling zombie killing?  What did you think about tonight’s latest “Infected”? Check out all our other ‘Walking Dead’ season 4 coverage, and join us next week for another all-new episode recap of episode 3, “Isolation,” on AMC!

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