A review of tonight's "The Walking Dead" coming up just as soon as I tell you the difference between beer nuts and deer nuts...

"She can't be around other people." -Carol

Well, that was a hell of a thing.

For a while there, "The Grove" felt like one of the weaker episodes of this half-season. It seemed uncertain how far to push the notion of something being seriously wrong with Lizzie — though there were early hints that she had problems pre-dating the apocalypse, like Mika telling her sister to look at the flowers and count to 3 "like you're supposed to" — versus sticking with the idea that she remained somehow confused after all this time and all the carnage.

But, of course, Scott Gimple was just setting us up for the massive stab to the gut that came when Carol and Tyreese returned to the house to find Lizzie standing over Mika's body, a bloody knife in her hand, Judith spared only because they got back as quickly as they did. (And Carol's line about how Judith can't even walk yet conjured up the horrifying image of a baby zombie crawling her way towards her next victim.)

Though the Lizzie story wasn't always the most gracefully told one this season, in part because of the limitations of the young actresses involved, this was gripping stuff because the burden wasn't on the girls anymore, but on Melissa McBride and Chad L. Coleman. Not only are they two of the stronger actors remaining in the ensemble — and if you have any doubt of this, please go watch the last 15 minutes of the episode again — but the lingering tension over Carol's murder of Karen and David added extra power to what was already a fraught situation.

The lazy way to go with that development would be for Tyreese to have become fully trusting of Carol — maybe even to have fallen for her, as the only adult woman in his life at the moment — and then feel betrayed as the truth comes out. Instead, the one situation winds up paralleling the other — just as Carol again has to bury a daughter figure who didn't have a mean bone in her body — as Tyreese comes to realize there are scenarios in this post-apocalyptic world where human beings have to make terrible decisions about individuals for the sake of the greater good. In the days gone bye, Lizzie is institutionalized, but all of society's institutions have gone kaput, and there's nothing to be done. Keep Lizzie around, and Judith and other people are constantly in danger. Abandon her, and she either dies anyway (and becomes a walker who could endanger others) or falls in with another group who couldn't possibly imagine a cute little blonde girl being the danger that Lizzie turned out to be. So Carol kills her, "Of Mice and Men"-style, and tells Tyreese the truth about Karen and David at a moment at which he can actually understand why she might have done such a seemingly monstrous thing for the good of the group.

It was a climactic sequence so raw and wrenching that even the usually exuberant Chris Hardwick appeared shaken up when we got the obligatory teaser for "The Talking Dead" at the episode's end.

Some of these season 4.1 character pieces haven't quite worked, but this one slowly worked itself up into something great and horrible. Definitely the highlight of this stretch of episodes so far — if you can call an episode that involves the murder of two sisters a highlight — and a reminder of the power of simplicity on this show, particularly when the actors involved are as good as McBride and Coleman. 

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.

NOTE: Like tonight, AMC isn't making this season's remaining episodes available in advance, so reviews will get done when they get done. This one wound up coming out pretty quickly, but I can't guarantee that pace for the next two Sundays.

But in the meantime, what did everybody else think?

Alan Sepinwall may be reached at sepinwall@hitfix.com