Actually, there are two foes that the group fights in "Them" that are more deadly than zombies, governors, or even passive-aggressive cannibals. The first is thirst, as the group has run out of water. The second is depression, as Maggie, Sasha and Daryl must decide whether surviving is even worth the trouble.
Given that TWD is mid-way through its fifth season, it seems kind of insane that this is the first episode that features the group lacking a basic resource like food or water. Obviously, most of the threats they face tend to more psychopathic and less implacable, which makes for more exciting television, to be sure, but it's weird that in the world of TWD you're much more likely to be killed by a lunatic in a tank than from starvation. "Them" is an excellent reminder that the world is a still a plenty deadly place even if you've gotten good at fighting the living and the dead.
Anyways, it's no coincidence that the group has run out of water as they've also more or less run out of tears. The deaths of Beth and Tyreese have hit everyone hard, but Maggie, Sasha and Daryl can't even cry about their losses. They've seen too many loved ones die, and mourned too much. Now, they're forced to wonder what the point of fighting so hard to survive is — when "living" mostly means watching the people they care about die. Pairing their emotional nadir with the relatively banal threat of dying of dehydration is a natural thematic choice — and it emphasizes their suffering significantly more than zombies do. And man, does the show do a great job making them all look like they're suffering, physically and emotionally. These people look rough.
I've always said that TWD is best when it's not talking, and "Them" is another great example: besides for a few quiet conversations, the episode allows the characters' appearance and demeanor speak for themselves. Watching them all shamble down the road — looking for all the world like zombies themselves — is a hundred times more effective than a scene where Rick addresses the group on the water shortage would have been. Seeing them try to dispatch a group of walkers trailing behind them by luring them into a ditch abundantly shows how exhausted they are; and having Sasha ignore the plan to vent her anger out on the zombies — endangering herself and others — ably indicates her desire for self-destruction. And Daryl… well, if Daryl putting out a cigarette on his own hand with no emotion in his face doesn't show you where his head is at, I don't even know, man.
Here's how bleak "Them" is — when feral dogs burst out of the woods to attack them, it's a good thing, because at least now the group has something to eat. But when the group discovers a pile of bottled water in the road, with a mysterious note reading "From a Friend," everyone is too distrustful, given all they've gone through, to drink any of it (well, Eugene is willing to risk it, but Abraham shuts him down). Happily, just at that moment, it begins to rain! And because nothing can ever go well on TWD, it suddenly begins to storm. Hard.
The group takes shelter in a barn Daryl had found while scouting, and it's here where the episode takes a turn for the crappy. It starts out so well, too — Rick says he used to feel bad for kids who are growing up during the zombie apocalypse, but theorizes that maybe since they're kids, it feels normal for them. This leads into a discussion of whether the world they're living should be considered the real world or an aberration; if it's the old world that should be considered the norm. Opinions differ, but it's an interesting debate. Then Rick starts telling a story about his grandfather in World War II, which ends with him stating, in all seriousness to his compatriots, "We… are the walking dead."
I guess it would have been slightly more jarring to have Rick let out a huge, fat, wet fart, than to bludgeon viewers over the head with the dual meaning of the show's title, but I would have much preferred the fart. I have no idea why one random episode in season 5 was the time the writers decided, "Hey! Let's say the title of the show in the show! Won't that be krayzeeeeeeee?!" but it's jarring and awful and nearly ruined what was a pretty good episode. At this point, an enormous herd of zombies starts banging on the barn door, presumably because despite being dead they have too much dignity to let Rick's ridiculously on-the-nose observation to stand. Of course, when the zombies threaten to break in, everyone rushes to keep them from bursting in, even Maggie and Sasha and Daryl. They may not know exactly why they're fighting to live, but at the end of the day, they're still fighters. It's what they do.
The next morning, Maggie and Sasha head out and discover that the storm uprooted trees, tossed zombies around willy-nilly, but somehow left the barn untouched. Maybe it's a minor miracle, but it's not the biggest surprise they get. No, that's when a kindly, clean young man named Aaron pops out while they've watching the sun rise, and politely asks if he can see Rick.
Who is this interloper? How does he know Rick? Can he be trustehahahaha ha ha ha ha — sorry, this is The Walking Dead, he obviously can't be trusted. We'll see what nefarious dealings he has planned next week, presumably. But whatever evil lurks in his heart, at least he probably won't do anything as heinously awful, as morally reprehensible, as calling anybody "the walking dead."
• In the episode's second shot, Daryl is digging in the ground for worms, and then eats one. It's totally bizarre, at least when you haven't yet realized he's so damn thirsty worm juice seems a reasonable option. It just seems like Daryl's suddenly developed a taste for worms.
• Father Gabriel tosses his little priest-collar thingie in a fire, and then feels super-bad when God makes it rain. I am deeply amused that Gabriel presumably believes God has unleashed a hellish plague of ambulatory corpses who feast on the flesh of the living, but was so concerned about Gabriel's collar-thingie that he made it rain in order to set him back on the right path.
• At one point, while searching a car, Maggie discovers a zombie in the trunk — a zombie that is bound and gagged. I'm having a hard time imagining a scenario where this wasn't a woman who was tied up while alive and put in the trunk, but who died in there and turned. Because why would someone bother to gag a zombie? It's not a "prevent you from biting" someone gag, it's clearly to keep them from calling out.
• Fun captioning when Glenn kills the trunk zombie: (flesh squelches)
• Eugene: "I honestly do not know if things can get any worse."
/wild dogs burst out of forest