Previously, Katara was the only Waterbender from the South Pole, there was a big scary Fire Navy ship outside her village, Yue shared some folktale mumbojumbo about the moon being the first Waterbender, and Katara learned how to Bend using her sweat. You might have guessed that this is an episode about Waterbending.
Currently, the Gaang is camped out in a forest somewhere, with Sokka telling ghost stories, complete with his own sound effects. The rest of the Gaang is nonplussed. Toph: "Water Tribe slumber parties must stink." ...I now want to know about Earth Kingdom slumber parties. ...and how the hell Toph ever had a slumber party. Katara, compelled to defend the slumber party traditions of her people, tells a story of her own, a "true Southern Water Tribe story". One that happened to her mother, apparently. There was a snowstorm, their mom realized her friend was missing, nothing but a fire in the fireplace when they went to look, ghostly spectre of mom's friend trying to get warm, empty house with smoke rising from the chimney "like little Nini is still trying to get warm." The Gaang is much more affected by this story. So when Toph says she can hear people screaming under the mountain, they assume the OH GOD DON'T EAT ME position, previously demonstrated in The Swamp. At least then the flora really WAS out to get them. Kind of. But after a minute, Sokka relaxes, thinking Toph's trying her hand at a jump scare. Voice: "Hello, children." Children: "*collectively crap their pants*"
A woman, who kind of resembles the Horrifying House Guest, has walked up behind the Gaang, presumably with the sole purpose of scaring the living daylights out of them. She introduces herself as Hama, and invites them back to her inn so they don't have to sleep in the woods. Because, as she warns them over tea, people have been disappearing in those woods. "When the moon turns full, people walk in...and they don't come out." So it's a forest of roach motels? Seeing that's she's obviously scared them completely stupid, she shows them to their rooms for the night. Sokka ends up drawing his sword at every creak and groan, telling Momo (how much do I love that Momo is Sokka's best friend now) that he doesn't think he'll be able to sleep.
But then again, he's Sokka. Hama and Katara wake him up the next morning to go shopping, because we all know that's Sokka's favorite pasttime. Katara says that one of the shopkeepers seems to "have a thing" for her. "You should go back and see if he'll give us some free komodo sausages." Hama: "You would have me use my feminine charms to take advantage of that poor man? I think you and I are going to get along swimmingly." In addition to the previous House Guest resemblance, Hama looks like the guy from The Tell-Tale Heart and has Azula's talon-nails. Surely this is a trustworthy individual.
Sokka overhears a merchant saying he can't get more ash-bananas (not ass-bananas as I originally heard, because I am twelve) because the full moon is the next night, and he can't lose another delivery boy in the woods. He decides it sounds like Spirit World shenanigans, and Aang resolves to figure out what they did to piss off the nature gods and fix it, because Avatar. Hama tells the kids to take the food back to the inn while she finishes her errands. Sokka comments that the town is "mysterious". Hama: "Mysterious town for mysterious children." Sokka: "That was not at all relevant to anything we were talking about. Thank you."
Sokka's Instincts seem to be acting up again, as he now suspects Hama of hiding something. Katara continues to doubt Sokka's Instincts. "She kind of reminds me of Gran-Gran." Sokka: "Then what did she mean, 'mysterious children'?" Katara: "She found four kids of indeterminate origin camping in the woods with a giant bison and a monkey, what would YOU think?" Sokka: "...touche." He resolves to look around, while Katara yells at him for being a snoop. Sokka yanks open a cabinet to reveal a bunch of marionettes, which honestly just made me think of Sasori (I was watching a lot of Naruto when I first saw this episode, sue me). Despite Katara protesting that that's not weird (spoiler: it totally is), Sokka finds a locked door in the attic that he takes as proof that Hama's hiding something. Which is in fact usually the point of a locked door. He looks through the keyhole and sees a box (Toph: "Maybe it's TREASURE!"), then proceeds to pick the lock...with...his sword? Okay, sure, why not. The box is locked too, and Toph uses her meteor bracelet to make a key. ...of course you've thought of that, Toph. Little delinquent. Katara and Aang turn to leave Sokka and Toph to their BFF crime spree, but come sprinting back as soon as Toph gets the box open.
Busted! Hama says she'll tell them what's in the box, and it turns out to be...a comb. "It's the last thing I own from growing up in the Southern Water Tribe." Apparently she heard Katara's Water Tribe ghost story, and bought all the food she did to make them a big Water Tribe dinner. As a surprise! Sokka apologizes for sneaking around (though not before pointing out that he was right), which Hama readily accepts. At the table, after Aang warns Toph off the sea prunes, Hama serves "five-flavor soup"...with Waterbending! Katara is practically exploding with excitement at this point, meeting a Waterbender from her tribe, and Hama explains that the Fire Nation wiped them all out.
Sixty years ago, the Fire Nation started raiding the Southern Water Tribe, back then something resembling a small town if not the booming metropolis of the Northern Tribe, climbing in their windows and snatching their Benders up. Turns out Hama was one of the Waterbenders that froze that ship where it was, and was the last Waterbender to be captured. (PS I'm just assuming this is Gran-Gran.) Sokka asks how she got away, and why she stayed in the Fire Nation, but Hama can't talk about it anymore. Katara says they lost their mother in a raid, and Hama offers to teach her some of the Southern Waterbending traditions. Katara, as is probably expected, enthusiastically accepts.
Hama talks about not being surrounded by your Bendable element - like when they were stuck in the desert that one time - and tells Katara she has to learn to control water wherever it exists. Like, say, your own sweat. But then she does a sort of sweeping move and pulls water out of the air around them. Not a lot, but enough to freeze into daggers and launch into a nearby tree. That's...oddly violent of you, Hama. Cool, but oddly violent. Katara is just in "OMG NEW WATERBENDING SKILLS" mode.
Aang, Sokka, and Toph are playing Nature Detectives. Aang says he can't see anything that would make a spirit mad at the villagers. Toph suggests the Moon Spirit just "turned mean". Sokka: "The Moon Spirit is a gentle, loving lady! She rules the sky with compassion! And...lunar goodness!" Toph: "Gee, Sokka, why don't you marry her?" Sokka: "...*sniff*" Aang asks a passerby about the kidnapper spirit, and is pointed at Old Man Ding as the only known witness of a lunar abduction.
Hama has brought Katara out into a field of bright red flowers, apparently called "fire lillies". Hama says they're one of her favorite things about living in the Fire Nation, and also that they're full of water. Precious, precious water. Katara mentions the Swampbenders, controlling the water in the vines, and Hama says you can take it a step further, pulling water out of a wide swath of flowers and using it to slice a nearby rock into slabs. When Katara laments the dead lillies, Hama says they're just flowers. "When you're a Waterbender in a strange land, you do what you must to survive." She plans to teach Katara her ultimate technique that night, under the full moon. Katara says that's dangerous, what with the vanishing people, but Hama doesn't think they have anything to worry about. Of course you don't, you creepy, creepy woman.
The rest of the Gaang goes to see Old Man Ding, who is boarding up his windows (and also protests being called old). As Sokka and Aang help him, he tells him about his almost-abduction. He didn't see a spirit, but something took hold of his limbs and started walking him towards the mountain, and him unable to control himself at all. But whatever had hold of him broke as the sun rose, and he hauled ass back to the village. Toph remembers the screams she heard, and surmises that the missing villagers are still under there. They take off towards where Toph heard the screaming, as Katara and Hama go for a walk in the moonlight. By which I mean Hama is hulking out, veins popping up in her arms as she stands under the full moon. "I've never felt more alive." Katara, that is the warning sign. She is a crazy, crazy lady, and you should run far, far away.
Toph leads the boys to the entrance of the cave in the mountainside, grabbing Sokka's hand to lead him down the pitch-black cave. There's at least a dozen people locked up down there, who tell them it was no spirit that led them there, but a witch. "She seems like a normal old woman, but she controls people like some kind of dark puppetmaster." Oh hey. Sokka: "TWO AND TWO EQUALS FOUR." He and Aang take off to stop Hama from whatever they think it is she's got planned, as Toph leads the captured villagers from the cave.
A...cat-owl? Fox-owl? I'm not sure. Anyway, it flies off as Hama starts monologing. In the Fire Nation prison, they went to extreme measures to keep the Waterbenders from having any way to defend themselves, but Hama could still feel the full moon's power each month. Eventually she realized that all living things have water in them - and like any other water, it can be Bent. And she learned how, developing the technique of Bloodbending. "Controlling the water in another body, enforcing your own will over theirs." She used it on the guard with the key to her cell, not bothering to free any of her fellow Waterbenders, mind, and waltzed right on out.
Katara has a problem with this. Hama says she doesn't have a choice; the power is already there. "It's your duty to use the gifts you've been given to win this war! Katara, they tried to wipe us out, our entire culture! Your mother!" Sounding kinda Jet there, Hama. ("Remember why you fight.") During Hama's tirade about fighting "these people" wherever they are and however they can, the penny drops for Katara and she calls Hama out on vanishing people every full moon. "They threw me in prison to rot, along with my brothers and sisters!" Yeah, and you did a bang-up job getting them out, too. Katara refuses to carry on Hama's technique, or to let her keep terrorizing the town. Hama responds by yanking Katara around like a rag doll. "I control every muscle, every vein in your body!" She throws Katara around a bit, presumably to make a point, before making her kneel as Katara begs her to stop. Hama just laughs a creepifying laugh, and under the full moon Katara pulls water from the grass beneath her and stands, under her own power, fighting off Hama's influence. I can only assume Yue's lending a hand here. Spiritually, I mean. "You're not the only one who draws power from the moon. My Bending is more powerful than yours, Hama. Your technique is useless against me."
Waterbender fight! Pulling water from the grass and trees (the latter of which sort of twist and explode when drained), Hama launches a veritable tidal wave at Katara, who just stops it with the palm of her hand. Sokka and Aang come running up, telling Hama she's outnumbered. "No...you've outnumbered yourselves." And she starts puppeteering the two of them at Katara. She dodges them and tries to take Hama out, but she shields with a sort of ring of water. (Hama used Aqua Ring?) Sokka starts swinging his sword at her, though at least he gets a warning off first. "It's like my brain has a mind of its own!" That's something I've often suspected about Sokka, honestly. She freezes Aang to a tree, apologizing immediately. Aang just yells "it's okay!" from off-screen, which cracks me up more than it probably should.
Hama pulls them both free of their restraints and launches them at each other, Sokka's sword straight out, but they stop just before impact. Hama goes rigid in the background, eyes wide and terrified, and as Katara lowers her arms Hama sinks to the ground. Toph runs up with the villagers then, and Hama is led off in chains. But she seems okay with this, saying her work's done. She stops, turning around to congratulate Katara. "You're a Bloodbender."
And under the full moon, Katara just sobs.
Next episode, who needs sleep?