A review of tonight's "The Walking Dead" coming up just as soon as I find a building that will burn...

"Thing is, they aren't all gonna make it." -Rick

Well, that's not something I was expecting to see happen anytime soon on the show, if ever.

The series' key philosophical conflict at the moment involves Rick's group trying to toughen up the pampered, whiny Alexandrians, who think their new ant overlords neighbors are being way too ruthless and dangerous. "Thank You" puts that conflict even more front and center than the premiere or last week's failed Wolves invasion did, by placing Michonne and Glenn in charge of a group of Alexandrians who are in way over their heads as they try to make it back home ahead of the stray zombie herd.

The show has struggled at times in finding the good balance in this debate. Obviously, Rick is right and the Alexandrians are wrong, but if you push that too far, then his people are all superheroes, and the Alexandrians are all strawman villains who deserve the idiotic deaths they walk into, like how the very first death in "Thank You" involves the guy who was loudly complaining about Rick's leadership only moments earlier. So when Rick warned that some of the group wouldn't survive the long walk, I figured the victims would all be redshirts, since the show's gone a very long time without killing off a core member of Rick's team. In particular, nobody from the initial group in the quarry outside Atlanta has died since Andrea way back at the end of season 3. "Walking Dead" had, by now, become a show where Anyone Can Die, Except If They're Near The Top Of The Call Sheet.

Then Glenn and Nicholas ran down that alley together.

And there was no way out, short of a massive cheat that "Thank You" wisely avoided.

Of the quarry survivors, Glenn's always been the one the show's done the least work in developing — the group's reliable, but not particularly interesting, backbone — but so much time has been devoted to his relationship with Maggie that he seemed more death-immune than many. Instead, he dies a pretty gruesome death, made worse because Nicholas once again is a coward and shoots himself in the head, without the decency to at least do the same for Glenn first. (The image of his guts being torn out looks nearly identical to what happened to Noah — also because Nicholas was a coward.)

Killing off Glenn (not even heroically, but in such meaningless fashion) not only jolts the show out of complacency — if the main characters are invulnerable and the Alexandrians are all cannon fodder, where's the tension? — but makes clear that for all of the self-righteousness of Rick and his people, even having superior training, equipment, and the right mental attitude won't always save you in this world. In a vacuum, Glenn is better-equipped to survive a zombie attack than, say, Heath. But Heath went down an alley where there was safety on the other side of the fence, and Glenn went down one where there was no way out.

There were some logistical issues in this one, tied mainly to the fact that Rick's original plan was so terrible (see below), but as a relentless "And Then There Were None"-style ordeal where the trained and the unqualified alike are doomed to watch people they care about die horribly, it worked extremely well.

And between Glenn's death and Carol very publicly taking out so many Wolves, maybe the surviving Alexandrians will stop complaining so much about how mean Rick is once he finally makes it back to town.

Which will likely still happen, despite the overwhelming odds he himself is facing in the episode's final shot, but which seems slightly less of a guarantee now that Glenn has finally fallen.

UPDATE: Or has he fallen? A lot of you have speculated that Glenn may have somehow survived this, and "Talking Dead" apparently treated the scene ambiguously. Given how tightly the show has clung to Glenn and the other remaining quarry folk, and given that the show has previously put Glenn into a situation (also involving Nicholas) where death seemed inevitable, only to have him miraculously escape, I suppose I shouldn't be surprised if he survives this. But the odds in this scenario were so overwhelming, and the whole point of the episode was that anyone can die when the situation gets bad enough, that it would be a spectacular cop-out if Glenn turns up in Alexandria an episode or two from now with some ridiculous story about how having Nicholas' body on top of him somehow prevented dozens and dozens of zombies from also eating him. It would signal that certain characters on the show are just invulnerable, make the emotional distance between them and any newcomers even greater, and turn the whole thing into an exercise in fan service, because Glenn is popular.

So stay tuned on that, I guess.

Some other thoughts:

* Now that we know the full nature of Rick's plan with the herd was just to drive them 20 miles up the road, I have to agree with my HitFix colleagues that this was a terrible plan, even before they had to turn the dress rehearsal into the real thing. There was a period where all those zombies were trapped in the quarry, and rather than lead them all outside, where a stray noise like that truck horn could lead hundreds of them off the path, they could have just filled the whole pit with kerosene and lit it on fire. Wouldn't have killed the zombies, but would have left most of them so physically damaged that they wouldn't be a threat anymore. This approach had too much risk for too little reward. Literally moving your problem on down the road only does so much, because what's to keep the horde from eventually drifting back in your direction?

* The Wolves attacking Rick in the RV appear to be the same ones Morgan chased out of Alexandria, but the choreography of those scenes makes it unclear whether they only have one gun (the pistol their leader grabbed as he was on his way out of town), or several guns. Which again gets back to the weirdness about the Wolves and guns. On the one hand, they're organized enough to set up something like the trap that nearly killed Daryl and Aaron last season, and being that good and still alive all this time later, you would think they've amassed a decent arsenal. On the other, they invade Alexandria with only machetes and knives, and lose despite the surprise factor because Carol and a few others have guns. So perhaps they have a code against guns, but then at least one of them grabs a gun and tries to use it against Rick, so... I have no idea. It's distracting.

* Given the deserved heat the show has taken at times over the years for its There Can Only One approach to African American men surviving in the group — and the larger horror genre trope of black characters not lasting very long — I have to assume it's not a coincidence that the last three people standing (even if one is leaning on the other two) on the perilous walk from the quarry back to Alexandria are all black. Maybe Gimple's finally taken that particular criticism to heart?

Before we go to the comments, it's time once again to explain how this blog's No Spoiler rule applies to this show:

1. No talking about the previews for the next episode.

2. No talking about anything else you know about upcoming episodes from other sources — and, yes, that includes anything Gimple and Kirkman have said in interviews.

3. No talking about anything that's happened in the comic that hasn't happened in the TV show yet. (Or anything that's been revealed, like character backstory and motivation.) As with "Game of Thrones," the goal is to treat "The Walking Dead" TV show as exactly that, and not as an excuse for endless comparisons with the comics. If you want to talk about the comics, feel free to start up a discussion thread on our message boards.

What did everybody else think?

Alan Sepinwall may be reached at sepinwall@hitfix.com

Alan Sepinwall has been reviewing television since the mid-'90s, first for Tony Soprano's hometown paper, The Star-Ledger, and now for HitFix. His new book, "TV (The Book)" about the 100 greatest shows of all time, is available now. He can be reached at sepinwall@hitfix.com