Oh, it had started as a wonderful day. A beautiful, late-summer morning, barely a cloud at the sky, and Katara had decided to take a walk. She had dressed as a regular commoner, messed up her hair, for she had numerous reasons for people to not recognize her (not least of them the drooling fanboys), and went on the lower ring of Ba Sing Se, to catch a break of the absolute "perfect" of the upper ring, and to remind herself that even with the was over, there were people who had hard time.

Though it was a difficult feat to accomplish at the crowded lower ring morning, she had somehow managed to separate herself from most other people, the only exception being a certain little boy, maybe five years old. There was nobody else on sight, and an eerie silence fell.

Then they were surrounded by men: The big, stupid kind, the kind usually being pushed around by someone smarter - Katara had been told not to judge a book by its cover, but it was hard to see these people as intellectuals - most of them armed with swords and clubs. And that was the end of the wonderful day for her. Some of them were leering at her, despite her clothing.

One of the men raised his hand, three fingers up, and grunted: "There three rules. Rule number one:" He dropped two fingers, "Scream, get hurt. Rule number two:" Two fingers up, "Fight back, get hurt." She wondered if she could win them all: She didn't carry any water with her, but there was a barrel of water nearby she could use. ... Yes. After all the things she had fought and triumphed, she doubted a band of ruffians could cause her much trouble. Even if they had benders.

"Rule number three-", the man continued, three fingers up, but this was the point where the boy mentioned before, also surrounded and almost crying with fear, had summoned up enough courage to leg it. One of the burly men surrounding them made a simple hand gesture, and though Katara saw what was coming, the poor kid received a direct hit to the chest by a pillar of earth that had risen to meet him: With a sickening crunch he fell to the ground, where he was picked up by yet another man. The thug who had been talking now faced Katara and grinned, as he finished: "Try to run, get hurt. Yer coming with us, both of ya."

Now she was facing the important question: Should she fight? After what she had just witnessed, she was burning with rage - and struggling to not show any of it to these men - and would have loved to exact her justice on them. But wherever they would be going would, most likely, be the base of operation for something evil and depraved Katara had no idea still existed. By going with these men, she could plug the cancer at its source.

And so she did. She did not fight back when the men grabbed her and tied her hands behind her back.

---

She was thrown to an empty cell, lost her balance, and fell rather painfully on the floor, but barely registered the pain: That poor kid had hurt so much more earlier.

After maybe ten minutes of walking with the thugs, Katara had found herself inside what had seemed like a small, insignificant building at the very edge of the city, but had turned out to be a moderately large underground complex, full of cells holding many men, women, and children, all of them more or less starved and dirty. She had been treated fairly well, all things considered, apart from one of the men slapping her, which stung a bit.

And now she found herself in an empty, bare, windowless cell, with wooden walls, stone floor, and iron bars. Toph would have liked it. The air was pretty dry: She tried to bend a bit, and only managed a few pathetic drop of water from the air around her. Not enough to bust her out.

Perhaps it hadn't been the best of ideas to come here? Now that she thought about it, maybe she should have defeated those men, and then have them tell her where their headquarters were. She might have lost the element of surprise, but she could have taken sizable amounts of water with her, perhaps even a friend or two. But what was done was done: Instead of panicking or letting fear take over her, Katara brought her tied hands from below her feet to her front, and took a meditation stance Aang had taught her a while back. She closed her eyes, and waited.

She didn't know how long it had been, perhaps an hour or two, when she was served lunch. It came in a cup full of something brown she didn't recognize. Despite the good breakfast, she had had plenty of time to become hungry again, and so she ate it: It tasted better than it looked - it was bound to, she thought. "Hope ya liked it, lass," said the man outside the cell who had served her with it, grinning. "It'll be all ye'r gonna get today." If only he knew: She made a mental note to eat plenty on the dinner, once she got out of here, for the sole reason of proving this guy wrong.

Another hour later, she heard other footsteps coming her way, and opened her eyes. The cell door opened, and a familiar man stepped in: This was the one who had hurt that boy. And he was grinning at her - why did every single man here insist on grinning at her like that?

"Well hi again, little girl," he said as he approached, in what he probably thought would be a seductive, sexy tone, but which came out sounding pretty disgusting for Katara. "Y'know, me and the boys had a bit of a game upstairs, to see who would have the priviledge of coming down here for you. And guess what?" He brought his hands to the wall on both sides of her, bringing her nasty face closer. It stinked like bison droppings.

"Let me guess," she growled. "You won?" It was obvious to her that this would be the time she made her move: Would she wait any longer, and there would be lifelong implications. She brought her hands to the man's chest, as he chortled and nodded in agreement.

She had been taught that bloodbending only worked during the full moon, which today wasn't. However, she had discovered by herself, that it was a possible move to accomplish even now, but much more difficult, and required physical contact, which she now had. She could feel all that water flowing under her fingertips, calling for her, screaming at her, telling her to free it.

She did. The man's grin became a face of terror, and his laughter turned into scream, as the liquid inside his body rebelled and escaped. From his nose, mouth, and flesh came streams of water, something Katara imagined to hurt more than a little, and when she was done, what remained was a wrinkled, mummified creature, writhing on the floor, barely alive.

She used her newfound weapon to cut the ropes binding her hand, and left the cell.

---

The sun had begun its fall when Katara had returned. She looked as dirty as she had been when she left, but she was cheerful and happy. She gave Aang a wide smile, to which he responded in kind.

"Where were you?", Sokka inquired. "I thought you were just going for a little walk. We were worried."

"Sokka, you don't need to be worried about her," Aang scolded. "She can handle herself better than you." The older boy scowled at him, but it was compeletely evident to anyone blind (or without an earth-sight) that Aang had been worried as well.

Katara made the long story short, just said that there were slavers and that she handled it. Sokka nearly choked on his sausage. Aang burst out the water he was drinking, and looked at her with wide eyes. "There were slavers at Ba Sing Se?", he asked, flabbergasted. "And I didn't know about it?"

"Well, you have been gone for a long time," Toph said. She had taken the news much better than the two boys. "It's been more than enough time for mankind to sink really low." Aang looked crestfallen, of the idea about how rotten humans could be, and how he couldn't deal with the problem himself.

"You... Didn't kill anyone, did you?", he asked her, after a second or two. Katara had helped herself for some oatmeal.

"Oh, no," she responded. "There were broken bones, frostbites, and one serious case of dehydration. But no one died. Oh and, Zuko," she threw a scroll of documents at the Fire Lord, who caught it deftly. "There's a big slave ring going on in Fire Nation. See that you deal with it."

"Is it so hard to say 'please'? I mean, I am the Fire Lord and all."

"Shut up, Zuzu."

---

Following an anonymous hint, the Ba Sing Se city guard raided an empty, abandoned building at the city edge, and had astonished at what they had discovered.

When they were questioned about it later, no one, neither slavers nor slaves, could give very much coherent information. Most were talking about a mist, a mysterious fog suddenly rising from the lowest floor of the dungeon. It had spread quickly throughout the entire building, bringing winter and snow with its wake, cutting slavers with frozen blades out of nowhere, freezing them to the walls and the ground - but leaving the slaves unharmed, merely cutting their bindings and opening their cell doors.

Some of them reported of seeing a ghost: A spirit of punishment, coming to exact justice to the wicked. There was one slaver, only one, who had seen the apparition properly, and claimed that it had taken the form of a young woman, or possessed one, using her as a vessel. She had looked him right to his eyes, he said, and her gaze had been the worst thing of it all. When he had looked at her, his blood had frozen: He had seen an ice age in those eyes.

When the Avatar was questioned about the spiritual matter of the case, the following morning, he had responded that yes, he knew of one being like that: "An angel of vengeance," he had said. "A creature of unrivalled beauty, but you really don't want to get on her bad side."