Joel Keller is one of the cofounders of the site Antenna Free TV and cohosts the weekly AFT Podcast.

As much as my fellow TV critics and I try to cram The Walking Dead into the same dramatic box as its AMC counterparts Mad Men and Breaking Bad, we know in our hearts that it’s not that kind of show. More importantly, it’s not what the show’s viewers—over 20 million of whom tuned into the season four premiere last week—want to see. The characters may be shallowly drawn and the acting a bit overwrought, but as long as characters we’ve gotten to know are in imminent danger of being eaten by zombies, TWD is compelling to watch.

But that hasn’t always been the case, which is why the virus—or whatever it is—that has infected the prison where the Georgia refugees have built a home has made the beginning of season four as nerve-wracking a situation as the group’s initial escape from Atlanta, for these three reasons:

1. It puts everyone in the show’s crosshairs.

By the end of last season, as the prison was secured, Woodbury was overrun by “walkers” and the evil governor (David Morrissey) was dispatched into the woods, it felt like things were getting a little too safe for some of the show’s main cast members. Daryl (Norman Reedus) had stepped up in Rick’s place as the group’s leader after the death of Rick’s wife Lori; the romance between Glenn (Steven Yeun) and Maggie (Lauren Cohan) was blossoming; even the surly Michonne (Danai Gurira) was becoming part of the family.

Everybody was just too safe, and safety equals boredom on TWD. Now, as the group is discovering that previously-eradicated illnesses are rearing their heads in the post-apocalyptic world, they now have to worry about 1, whether they or the people they love will die from that disease and 2, whether they’ll come back as a walker and attack the survivors, as zombified teen Patrick (Vincent Martella) did at the beginning of last night’s episode “Infected”.

2. It allows the survivors to turn on each other.

As we found out last season with the Woodbury storyline, living humans are as dangerous to survivors of a zombie uprising as the undead themselves. And in the time lapse that occurred between the third season finale and where we are in the fourth season, I’m sure there was a lot of kumbayah amongst all the routine walker-killing maintenance and pig farming. Luckily, this all took place off-screen, so we didn’t have to see it; anyone who endured the endless season two episodes at the farm of Hershel Greene (Scott Wilson) knows how deadly to the show this can be.

But with this virus going around, people are going to start to turn on each other again. People will rat each other out if there’s even a suspicion of an infection, and maybe people won’t wait for the person next to them to die in order to stick a sharp object in their eye to keep them from rising once again.

We already saw evidence of doubt creeping in when Tyreese (Chad L. Coleman) didn’t want to go along with the community’s council when they told him to stay away from his new girlfriend Karen (Melissa Ponzio) as it looked like she was getting sick. As it turned out, Karen ended up dying from a bad case of the set-on-fires, which is another ball of terrifying wax for us to deal with (as is the person feeding rats to the walkers in order for them to mob one spot along the prison fence… has the governor been baiting them?).

3. It gets Rick back in the game.

Rick relinquished his leadership mantle because Lori’s death traumatized him so much, but also because he was hating how his example was making his son Carl (Chandler Riggs) into a dead-eyed killer. But as wooden as Rick can be sometimes, and as effectively as folks like Daryl and the formerly-meek Carol (Melissa McBride) have stepped up to fill the void, the group runs better when Rick is in charge; as Daryl told Rick in last night’s episode, without him, they wouldn’t have even gotten to the point where they had to defend their prison community.

So, at the end of the episode, when Farmer Rick picked up his six-shooter and gave Carl permission to arm himself, as well, things were becoming right in the Walking Dead universe. The show needs Rick to be the leader, even if he’s doubting his sanity or his ability to stay human in a world where even kids need to be taught knife-wielding survival skills. It’s good to know that Rick has been snapped back into taking up the good fight, even if it screws up both him and his son for life. It also puts him in harm’s way, and, as we’ve already said, what good is the show unless everyone on it could die at any second?

The Walking Dead airs Sundays at 9 PM Eastern on AMC.