The Undying Fire: City of Secrets

by Boogum

Book 3. It started with a battle for the Outer Wall. It ended with blood and a blackened throne. Ba Sing Se changed all of them, for better or worse.

3. The Plan

"I see it!"

Zuko perked up at the sound of Aang's shout. He joined the others at the front, leaning over the saddle to get a better look at Ba Sing Se. His eyes widened slightly. The wall was huge: a massive expanse of stone that stretched high into the sky. According to his uncle, this was only the outer wall as well, designed to be the first line of defence to protect the farmlands and smaller settlements. Ba Sing Se itself was hidden within another wall, and then there were several more that barred the way to the palace. Even from this vantage point, Zuko could only see the tips of buildings in the distance.

Iroh heaved a sigh. "I never thought I would see this place again."

Something tightened in Zuko's heart. Right. This was the wall his uncle had breached during the siege of Ba Sing Se. It was also the place where Lu Ten had been killed. Zuko made an awkward motion as if to reach for his uncle. Comforting people had never been his thing. It was his uncle who had always done the comforting for him.

"I'm sorry, Uncle," he said in a halting voice. "Being here must give you bad memories."

He had spoken quietly enough so only his uncle should have heard, but Toph still caught his words. She had taken a liking to Iroh, fondly naming the older man "Gramps" and treating him like a pseudo uncle. That was perhaps why she decided to poke her nose in and ask what was wrong. She normally didn't bother much with emotional things, let alone other people's problems.

"Did something happen here in the past?" Toph asked with all her usual tactlessness.

"Butt out!" Zuko snapped. "This doesn't concern you."

"It's okay, Nephew. These children have a right to know who is travelling with them."

"But—"

Iroh shook his head, silently telling him to step down. Zuko sat back and folded his arms across his chest. It was hard to stay silent—hard because he also missed his cousin and outsiders had no right to go opening old wounds for the sake of their own curiosity. These brats were just being nosy.

"So?" Toph prompted. "What's got Sunshine's loincloth in a twist?"

Iroh gave a strained smile. "You'll have to forgive my nephew. He can get a little protective."

Zuko blushed and averted his face. He just didn't want to see his uncle in pain. Was that so wrong?

"What happened?" Aang asked. He wasn't quite as tactless as Toph, but it was clear he was curious.

Iroh's gaze took on a faraway expression. "I mentioned that I once thought it was my destiny to conquer Ba Sing Se. Many years ago, when I was still a general, I led a siege on the city."

Toph sucked in a small breath. "The Six Hundred Day Siege of Ba Sing Se. I remember hearing about it when I was younger. That was you? You're the Dragon of the West?"

He nodded, though he didn't look happy. "I'm not proud of my past. I had always believed that victory would make up for any losses, but when I lost my own son ..." He sighed. "I spent six hundred days trying to conquer a city on a foreign land. My son died in the struggle to breach the walls. Suddenly, it all seemed so pointless."

A hush followed. It was the kind of silence layered with a multitude of reactions: the realisation that the kindly old man who travelled with them had not been quite so kindly in the past; the reminder that both Iroh and Zuko were Fire Nation and had, in their own way, helped to cause some of the suffering in the world. But there was also the sympathy that came with hearing about the loss of a loved one.

"So that's what happened," Toph said softly. "I always wondered why the Fire Nation army left just when they had got a foothold."

Zuko clenched his hands into fists. "Well, now you know."

"Nephew."

Zuko made a sour face at the warning tone. So maybe he was being too snappy. A part of him even knew that Toph and the others didn't mean any harm, but still. Couldn't they see that this subject was upsetting Uncle?

"Anyway," Iroh said, "we should just focus on getting inside the city."

"Are you sure it's a good idea for you to come back here?" Sokka asked with a frown. "What if someone recognises you?"

Iroh rubbed his chin. "Zuko and I have discussed this. It is dangerous for me to be in the Earth Kingdom: the people have every right to hate me, and there are many who would like revenge for what I did as the Dragon of the West." He spread his hands. "I'm afraid that does mean I will be limited in what I can do for you while we are in Ba Sing Se."

"What do you mean?" Aang asked, tilting his head.

"We'll be using fake identities," Zuko explained. "I will be Lee and Uncle will be Yingjie."

"That means we cannot support you as firebenders." Iroh met Aang's gaze. "Exposing our identities will only cause complications. I will help you come up with a plan to defeat Azula and her army. I will even fight if it comes to that, but it will be better if I do not participate as a bender in this battle." He glanced at each of them. "I'm trusting in you all to not let it come to that."

Aang nodded. "I understand. We'll do our best."

"I'm sure you will," Iroh said with a smile. "I have faith in all of you."

Zuko folded his arms. "Azula's army will be ready to attack by tomorrow. That doesn't give us a lot of time to put a plan into action. Plus, Aang still hasn't been able to go into the Avatar State."

"We'll make it work somehow," Katara said, ever the optimist.

Sokka placed his hand on Aang's shoulder. "Katara is right. Aang has done fine in battles so far even without the Avatar State. Besides, this time we won't be on our own. Once we speak to the Earth King, we'll have an army on our side."

"You'd better hope you're right," Zuko said grimly. "I won't forgive you if you put my uncle in danger."

Toph punched him in the arm. "Aww, Sunshine, you really do care."

Zuko's face heated. "Shut up."

The two were still bickering when Appa swerved, rolling up onto his side. Gravity kicked in with a rush of sickening butterflies. Zuko panicked and gripped the saddle. A yelp next to him had him grabbing the back of Toph's tunic to stop her from falling off.

"Thanks," she gasped.

"No problem."

Meanwhile, Sokka, Katara and Iroh were similarly holding onto the saddle. All of them looked a bit pale.

"Everyone okay?" Aang called over his shoulder.

"Just peachy," Sokka muttered. "A little warning next time would be nice. What the heck were you doing?"

"Sorry," Aang said, still facing the front. "There was a—"

He gasped and jerked on the reins. Appa pulled up, and this time Zuko saw the giant slab of rock that went sailing past.

"I think we're being attacked," Aang said.

Sure enough, several more rocks flew at them. Appa swerved and ducked, spiralling through the air with surprising agility for such a large beast. Sokka complained loudly as he held on for dear life. He demanded to know what the heck those jerks were thinking to attack the Avatar.

"We've come here to help you!" Sokka yelled, then yelped when Appa jerked to the left, almost throwing him off.

Katara clung to the saddle like a frightened monkey-cat. "Don't tell me Ba Sing Se is like Chin Village!"

Sokka's eyes widened. "You mean they're actually trying to hit us because we're with the Avatar?"

"Oh, I doubt that," Iroh said mildly. "I don't think it would matter who we are. The fact is that, to those soldiers down there, we're an unknown group of people who are trying to get into the city."

Zuko peered over the saddle and saw green-clad soldiers lined up on the Outer Wall. Catapults had been mobilised in strategic positions, which the soldiers used, along with earthbending, to fire the massive rocks. There were archers as well. Appa and Aang were doing a good job of avoiding the projectiles, but it was only a matter of time before their luck ran out. Even Momo gave up when an arrow came too close. He screeched and hid himself inside the front of Zuko's tunic, quivering like a furry ball.

"Uh." Zuko frowned down at the round-eyed face peeking up out of his tunic.

"Stop taking up all the room, Momo," Toph grumbled.

Zuko just blinked. He had a lemur hiding in his shirt and a little blind girl attached to his side. Since when did he become the human security blanket?

"Hey!" Sokka yelled down at the soldiers. "Quit firing stuff at us! Don't you recognise this bison? We're not your enemies!"

"I don't think they can hear you," Katara responded dryly.

Aang swivelled around on his perch and shoved the reins at Sokka. "Here. We're going to get knocked out of the sky at this rate."

Sokka swallowed and switched positions with Aang, who jumped onto Appa's head and used airbending to create a shield around them. The wind currents redirected anything that came close, just like a reversed tornado. It was pretty impressive. The Earth Kingdom soldiers must have thought so as well, as there was a sudden lull in the number of projectiles being thrown. Zuko glanced over the side and saw that a lot of the green-clad figures had stopped and were now pointing or just staring up at the wind shield.

Aang lowered the shield and took a deep breath. When he spoke, his voice was magnified beyond that of a normal human. "Please stop attacking! We are not your enemies!"

One of the figures stepped forward and spoke into a megaphone. "If you're not our enemies, then why did you try to fly over the wall?"

"We need to speak with the Earth King!"

The man on the wall guffawed. "The Earth King? Who do you think you are, kid?"

Aang stood up straighter. "I'm the Avatar! My friends and I bring urgent news! Please, you must let us pass!"

There was a pause as the soldier turned to discuss something with some of the other men gathered on the wall. Finally, he turned back to them and spoke into the megaphone. "Come down here! We'll take you to General Sung!" A pause. "Uh, but that big monster can't come."

Aang muttered something about how Appa wasn't a monster, but he seemed to understand that clarifying this point wouldn't help the situation. So, he patted the bison on the head and apologised for the Earth Kingdom soldiers' rudeness. "I'll make it up to you later, buddy," he said, giving Appa a hug.

Appa rumbled in his gentle way and descended so that everyone could clamber off onto the wall. Toph grinned so widely when her feet touched the ground that it looked as if her face might split. Momo also relaxed enough to emerge from Zuko's tunic and instead moved to perch on his shoulder. As for Zuko, he was just glad that they were all in one piece.

"This way," the guard said, gesturing with his hand.

oOo

Zuko was frustrated. As far as military leaders went, General Sung did not have Zhao's reckless, over-aggressive calibre, but it didn't seem like he had a good hold on the situation either. Sung had confessed he was aware of the Fire Nation's plans to attack. He also seemed to think the city's defences would be enough. That was worrying. Azula had studied every battle plan she could get her hands on with meticulous detail. She would have factored the wall into her calculations. Plus, the army that she had taken control of had been coming up with a new strategy to invade the city. There was no way they were going to rely on manpower alone.

"So you don't plan to do anything to prepare?" Zuko demanded. "What if the wall is breached? What then?"

General Sung's drooping moustache twitched. "Who are you?"

"What does it matter? Princess Azula isn't going to be stopped with a wall and a few measly rocks and arrows. Defence tactics won't work alone!"

The moustache bristled even more. "Avatar, I invited you to speak with me out of courtesy, but that is all. Please keep your friend in line. Need I remind you that I am the general here?"

Zuko opened his mouth to retort, but Iroh held him back with a warning grip.

"Let it go, Nephew."

Zuko tensed, still worked up that this idiot of a general was the one guarding the Outer Wall. Generals held people's lives in their hands; their choices would decide who would win or lose, live or die. It was ridiculous that such an incompetent man should hold the title. Yet, even then, Zuko understood that arguing would not solve anything. After all, the last time he had spoken out of turn had led to an Agni Kai that had seen half his face burnt off. Just the thought made an involuntary shudder sweep through him.

"Nephew?"

Iroh's voice was soft with concern. Zuko shrugged himself out of his uncle's hold. He bowed stiffly to the general, careful to place his hands together as people did in the Earth Kingdom.

"Please forgive me for my rudeness," he said with well-practiced politeness. "I did not mean to speak out of turn. I simply request that you reconsider your offensive strategy." Zuko kept his head low. "Princess Azula will have factored the wall into her plans. I do not wish to see more people get hurt than necessary."

General Sung opened and closed his mouth a few times like a koi fish. "Uh, well, of course I won't be relying completely on the wall. I have an elite platoon of earthbenders called the Terra Team under my command. They will be our main attack force."

Zuko straightened to his full height and fell in line with the others. He still had his doubts, but he chose to stay silent. Instead, it was Toph who spoke.

"The Terra Team, huh?" She blew her fringe out of her face. "Are these guys really that good?"

"Of course. That's why there is nothing for you to worry about." He smiled at Aang. "Thank you for visiting, Avatar, but we do not need your help."

Katara and Sokka exchanged a speaking glance. It seemed that no one had much confidence in General Sung or his Terra Team. Even Aang looked unhappy, though he was diplomatic enough not to push the matter. Instead, he asked if it would be okay if they stuck around for now, just until the battle was over.

"I know you have everything under control," Aang was quick to add, "but I'd like to be here to help just in case."

General Sung chuckled. "If you wish, but your help will not be necessary."

"That's fine." Aang smiled. "I don't enjoy fighting anyway."

The general couldn't argue with that, or maybe it was just that he was reluctant to tell the Avatar to get lost. Either way, the group was allowed to stay. They were shown to a room for important guests in the barracks, but were warned that they could not venture beyond the wall.

"I'm sorry," the same guard who had first greeted them explained, "but until you are given clearance, we cannot let you enter the city. Please keep that flying creature away as well."

"His name is Appa," Aang grumbled. "He's my bison."

"Then please keep Appa the bison from going past the wall," the guard said, straight-faced.

Aang blew his cheeks out in irritation. "What am I supposed to do with him then? Are you saying I just have to leave him outside by himself?"

"Be grateful that we have not already taken him into our custody. That creature is a complete breach of protocol. If we hadn't been there to stop you, you could have flown straight to the palace."

Aang looked like he was about to lose his temper, but Katara was quick to step in and calm him down. She turned to the guards with an appeasing smile.

"What Aang is trying to say is that Appa has been flying for a long time and doesn't like to be left on his own," she explained. "Isn't there a place he can rest?"

One of the other guards, a young, fresh-faced soldier, cleared his throat. "Uh, we could try to fit him into the old stables. It used to be used for ostrich-horses, but since the creation of the monorail, we stopped keeping animals there."

Zuko folded his arms across his chest. "That won't be necessary. I'll stay with Appa outside the wall. That should be fine, right?"

Aang blinked at him in surprise. Zuko mouthed that he would explain later, then turned back to the guards. Both men agreed that this would be fine, though the higher-ranked one said that someone would still be placed with Zuko to ensure that neither he nor Appa crossed the wall.

Zuko made a tsking noise. "Do you distrust us that much? I'm just going to keep the bison company. It's not like I plan to fly to the Earth King."

The response he got was that rules were rules. Avatar or not, they would not allow protocol to be breached. Zuko pursed his lips—all this talk of rules was really getting on his nerves—but then he just shrugged. He knew a losing battle when he saw one.

"Fine," he said, spreading his hands. "Assign a guard to me. It makes no difference."

With that settled, the higher ranked guard said that someone would be back later to finalise the arrangements. It wasn't explicitly stated, but Zuko got the impression that none of them were supposed to leave the room until the men returned. So much for the Avatar's celebrity status. These people really didn't trust them one bit.

Aang bounded up to Zuko once they were all alone. "Hey, what was that about before? Why did you—"

Zuko clamped his hand over Aang's mouth. "Not so loud," he scolded. "They've probably got someone listening in on us."

Aang's eyes widened. He said something, though it was too muffled to understand.

Zuko removed his hand. "Look, I think we can all agree that this set up sucks. That General Sung guy doesn't seem very competent, and I can't say I have much faith in this supposedly 'elite' Terra Team. The fact that they're treating us this way is a bit weird as well."

"Can agree with that," Sokka said frankly.

Katara's brow creased. "Then what are you suggesting we do? You heard General Sung. He won't let us help."

"That's why I'm going to infiltrate Azula's army tonight," Zuko said. "If we can get a better idea of her plans, maybe we can come up with our own counterattack."

"Are you insane?" Katara demanded. "You can't do that! What if you get caught?"

"I'm good at stealth," Zuko reminded her. "No one will even know I was there."

Iroh frowned. "I don't like this plan. It's too dangerous."

"It's necessary," Zuko argued. "Do you really want to sit around here and wait for the general to get desperate enough to ask for help?"

Aang bit his lip. "Zuko does have a point. I don't like the fact that we can't do anything except wait. It would be good to at least know what Azula is planning."

Zuko met his uncle's worried gaze. "I know you think I'm being reckless, but I've actually thought this through."

"Have you really?" Iroh placed his hands on Zuko's shoulders. "I know I said it was important to protect Ba Sing Se, but your life is far more precious to me. Do not put yourself in danger so willingly."

Zuko's cheeks warmed. He couldn't deny that it was nice to have his uncle worry about him, but still. He was determined to follow through with his plan. Sitting around and waiting had never been his forte. Zuko was a man of action, and right now he wanted to be as prepared as possible to counter his sister's attack. After all, Aang wasn't even in top form right now. If something went wrong and Aang was hurt or if Iroh was forced to join the battle, the repercussions would be so much worse.

"Please, just let me do this," Zuko said softly. "I know what I'm doing."

Iroh refused to budge. He said that he had let Zuko go alone once to infiltrate the North Pole, and look what had happened there. He would not make the same mistake again. Besides, a guard was going to be assigned to Zuko, not to mention everyone on the Outer Wall would be watching to make sure Appa didn't fly anywhere. They'd get suspicious if they saw a bison heading in the direction of the Fire Nation ships.

"That's why I'm going to leave at night," Zuko said. "I can deal with one guard. I won't let anyone else see me."

Iroh was still adamant that it was too risky. In the end, it took Katara promising to stay with Zuko and Appa to make them drop the matter.

"The guards will get suspicious if Zuko changes his mind about staying with Appa outside the wall," she explained. A smile curved her lips. "Don't worry, I won't let him go anywhere."

Zuko scowled at her, but Iroh was quite happy to accept this alternative plan. He knew that Katara was a responsible girl, not to mention had already shown that she did not agree with Zuko's stealth mission. So, when the young, fresh-faced soldier returned and explained that he had been assigned as their guard, even Zuko couldn't complain when Katara said that she would join them. The matter had been settled. It was as simple as that.

"There's no need to look so moody," Katara told him later. "I'm only doing this for your sake."

She got an even darker scowl for her efforts. No, Zuko was not happy with this decision. His plan was the best course of action. It annoyed him that she had interfered.

Toph smiled as she watched the two. "Maybe I should join you guys as well."

"Why?" Zuko snapped. "You also don't trust me?"

Toph cracked a grin. "Nah, I'm just curious. I think tonight is going to be pretty interesting."

His brow furrowed. He didn't understand what she meant, but Toph refused to elaborate. She just smiled knowingly and patted him on the arm.

"Good luck, Sunshine. Make sure you and Sugar Queen don't stay up too late."

She cackled, as if she'd just said a great joke, and then carried on walking to join the others. Zuko's frown deepened. Somehow, he got the feeling that he was missing something.

oOo

Stars winked to life in the night sky. Zuko sighed as their guard led him and Katara to a place where they could rest with Appa. The area outside the wall was barren. Most people used the ferries to get in and out of Ba Sing Se these days, so little had been done to cultivate the land or make it hospitable. Because of that, the mismatched group ended up having to sleep with no shelter. True, the soldier had tried to create an earth tent for them, but Appa had never liked enclosed spaces and had kicked up such a fuss that they had decided sleeping under the stars would be better. Zuko was beginning to regret saying that he would keep the bison company.

"I'm really sorry about this," the soldier said, blushing a little in embarrassment. "I know that you don't need a guard, but rules are rules."

Zuko resisted the urge to roll his eyes. He had been hearing that phrase for most of the day. It was against the rules to let civilians be on the wall, so they had been stuck with a guide whenever they left their assigned room. Even outside the wall, they got given a minder. It was annoying, especially since he couldn't leave to carry out his plan now.

He threw a half-hearted glare at Katara, who was sitting opposite him. A part of him still believed that he could have won his uncle over had she not interfered. Maybe. Either way, she seemed unaffected by his scowls. She chatted happily to the soldier, asking him about his life and what it was like to be a guard on the Outer Wall. It was only when Zuko relaxed enough to actually listen to their conversation that he realised she was stealthily getting information out of the man.

The soldier told them that his name was Changpu and that his family were pig-chicken farmers, though he had always wanted to join the army. He also admitted that the Terra Team was much smaller than it used to be and that General Sung had only recently been promoted to his role. Changpu hadn't wanted to speak bad about his superiors, but he confessed that he was worried. He wasn't the only one who felt that way either. General Sung had a habit of floundering when he got flustered and never really got anything done. That wasn't a trait people wanted in a leader.

A blush stained Changpu's cheeks. "Uh, but I'm sure he's actually a great general. I mean, there has to be a reason why the Earth King promoted him, right? We just haven't had a proper chance to see him in action. Maybe he'll surprise us tomorrow."

Katara frowned. "Is that really what you think?"

Changpu scratched his cheek. "I guess."

Zuko could only stare at her in a mixture of surprise and reluctant admiration. He couldn't believe that she had managed to get so much out of Changpu in so little time. It reminded him of Azula's uncanny knack to twist people around her finger. Both girls could be very charming when they wanted, though Katara favoured kindness instead of intimidation. She was also more sincere with her interest. Zuko got the sense that a lot of her cunning was unintentional. Well, mostly.

She smiled at Changpu. "I'm glad we got to have this conversation, though I am sorry for what I have to do next."

He scrunched his nose. "Huh?"

She responded by placing her hand, now sheathed in glowing water, against his forehead. The light flared brighter. Instantly, Changpu's eyes rolled back up into his head and he collapsed into her arms. Zuko blinked. Then he blinked some more. What the heck?

"Why are you just sitting there?" Katara demanded. "Weren't you the one who wanted to infiltrate the Fire Nation army? Hurry and help me tie him up. I don't know how long the healing sleep will last."

Zuko's jaw dropped. "You—I thought you—"

She threw him a grin. "Had you fooled, didn't I?"

"Well, yeah, but—"

Her expression sobered. "I actually agreed with your uncle at first. This really is a stupid, reckless plan, but then I realised that you also had a point. We can't just sit around and wait for General Sung to see his mistake. There's too much at stake." A flash of mischief entered her eyes. "Besides, two benders are better than one, right?"

Zuko pressed his palm to his forehead. "No way. It's one thing for me to go, but your brother and Aang will never forgive me if I let you come."

"This has nothing to do with them. Aang and Sokka don't have a say in what I can or can't do. I make my own decisions."

"I can see that, but—"

Katara raised her chin. "Look, we can stand here and waste time arguing about this or you can just accept that I'm coming. Either way, you won't be going alone."

Zuko sighed and pinched the bridge of his nose with his forefinger and thumb. "Do you even know how to use stealth?"

Colour dusted her cheeks. "Well, I haven't been trained or anything, but I promise I won't be a burden."

He raised his eyebrow. It was obvious that he did not believe her.

"I'm serious," she assured him. "You're going after the ships, right? In case you've forgotten, I'm a master waterbender." A smile curved her lips. "I'm sure you'll find me useful."

Zuko held her gaze for a moment before turning away. "Fine," he said. "Come if you're going to be so persistent. You're right that we don't have time to argue about this."

"Great!"

With that decided, they tied up Changpu with the rope that had been hidden in Katara's pack. Zuko then handed her a set of black clothes.

"You should put these on," he said. "They might be a bit big, but it'll make it easier for you to avoid being seen." He gestured at her Water Tribe attire. "That blue stands out too much."

She nodded and started loosening the ties on her robe. Zuko left her to it and smothered Appa in dirt and dust so that the bison's white fur was dulled to a brownish colour. Now they would be more camouflaged.

"Sorry," Zuko murmured. "We'll clean you up when we get back."

Appa gave a low rumble. It seemed he didn't mind being a bit dirty if it meant he got attention later. Katara joined Zuko on the saddle, now clad in black. His mouth quirked at her appearance. The tunic and pants were indeed too big for her. The bottoms drowned her feet in fabric and the sleeves drooped over her hands. She didn't look like much of a threat.

"Are you sure I can't wear my clothes?" Katara asked. She moved her hands so that the sleeves flapped around like wings. "I feel like all this fabric is just going to get in the way."

Zuko grabbed her wrists and rolled the sleeves up, then tied the fabric in place so they wouldn't fall down again. He raised his eyebrow at her, as if to ask if she was capable of doing the rest. Katara swatted his hands away.

"Alright," she said. "I should have thought of that sooner. No need to be patronising about it."

Zuko ignored this barb and settled onto Aang's usual perch. He hadn't directed Appa before, but he thought he'd got the gist of it from his observations. It couldn't be that much different from riding a komodo-rhino. He gathered the reins into his hands. "Yip, yip."

Appa took flight, blending in with the night sky thanks to his darkened fur. Zuko's pulse quickened as he waited to see if anyone from the wall would spot them. No one did. All had gone according to plan. For now, they were in the clear. Zuko just hoped their luck would continue.

oOo

"Those must be the ships," Katara murmured.

Zuko nodded. There were several Fire Nation vessels moving on the water, lights dimmed to avoid drawing too much attention. Bulky silhouettes could be spotted on most of the decks. Some kind of military cargo? He noticed that none of the ships seemed to bear the flags or royal insignia to show that there was royalty aboard. If Azula was down there, she had either decided to go incognito or had simply hitched a ride with a ship that was already heading for the city. He thought the latter more likely given that she had been travelling by land the last time they had seen each other. Boats were a much slower mode of transportation; she wouldn't have had the time to reunite with her own war vessel and get to Ba Sing Se to meet them.

"Which do you think the princess is on?" Katara asked.

"I'm not sure," Zuko admitted, "but that's the ship we want. She'll have copies of her battle plans there. We'll just have to be careful to avoid running into her."

Katara raised her eyebrow. "Are you really trying to avoid her? You could have gone to the base camp, right? General Sung did say it was on the coast. It would have been easier."

Zuko shook his head. "Azula doesn't like to share her plans until the very end. She's always worried that people will botch it up somehow or betray her." His expression turned grim. "Regardless of what the army officials decided, she'll be the one to have the final say."

"Then what should we do?"

"For now, let's get a closer look." He got Appa into position as he spoke. "I want to check out the cargo on board anyway."

Katara nodded. The two of them pulled their cloth masks up to hide their faces, then jumped over the side of the saddle. Wind rushed in Zuko's ears. Katara used her bending to make the water rise up and catch them, avoiding any sound of a splash. She guided the water lift to the railing of the closest ship so they could step onto the boat without any trouble. No soldiers were in the vicinity right now. So far so good.

Zuko gestured for her to keep an eye out and made his way towards one of the covered cargo. He lifted up the fabric to see a Fire Nation tundra tank. A crease formed on his brow. Tanks had become a standard tactic for the Fire Nation when carrying out an invasion; it was no surprise that Azula wanted to use them. Still, something didn't sit right. Just by doing a rough count of the bulky silhouettes, he knew that this force would likely not be enough to breach the Outer Wall of Ba Sing Se. Cause damage, yes, but Ba Sing Se's wall was much thicker and more durable than the ice one that the tanks had destroyed in the Northern Water Tribe. He couldn't imagine her making such a miscalculation.

Footsteps sounded from close by. Zuko froze. The sound was heading in his direction. He released the cloth and moved with cat-like silence, grabbing Katara by the waist and pulling her up with him so that they were lying flat on top of the tank. Just in time. A guard walked past as they settled into hiding.

Katara let out a breath. "That was close."

"Come on," Zuko said, already moving to jump down. "I want to search the ship more."

She joined him on the deck. They decided to head for the captain's cabin. All the important documents would be stored there and, at the very least, they would find someone who could give them decent information. Both teens were careful to avoid the soldiers patrolling on night duty. Zuko had warned Katara beforehand that it was better not to attack anyone unless it could be helped. Immobilised bodies were eventually found, after all. The last thing they needed was for the alarm to be triggered. Unfortunately for them, the captain's door turned out to be locked.

"This way," Zuko said, tugging on her wrist.

He jumped onto the railing and began a spider-monkey's crawl along the outer part of the ship, clearly intending to break through the window. Katara stared at him for a moment and then created a water lift for herself.

"I think this way will be easier," she said, straight-faced.

Zuko had an odd urge to continue climbing if only because he just knew she was teasing him. Still, this wasn't the time to get all stubborn and prideful. Speed was of the essence. The longer they dallied, the higher their chances of being discovered. He let go of the ship and joined her on the lift. She manipulated her element to take them close to the captain's window. As he had expected, the window was ajar. The night was muggy and Zuko knew from experience how stuffy boats could get. A glance inside revealed only one person: a man with well-groomed sideburns who was idly flicking through a scroll. Well, at least it wasn't Azula.

"Ready?" Zuko asked.

Katara nodded.

He took a breath and forced the window open, rolling into a crouch to allow her to follow up with a water attack that pinned the captain against the wall. Zuko was moving in a split-second, lunging forward to slap his hand over the man's mouth before a scream could escape. With a simple curl of her fingers, Katara switched some of the water to ice, creating sharpened daggers that hovered threateningly in front of the captain's face.

"Where are the battle plans for the invasion of Ba Sing Se?" Zuko demanded. "Nod if you have them on this ship."

The captain's eyes bulged. He tried to break free of Zuko's grip and perform a bending move, but Katara once more slammed him against the wall. The jolt was so hard that it made the man slump a bit, clearly dazed. Zuko blinked. He had forgotten that she was much stronger at night.

"Where are the plans?" Katara growled. She inched some of the ice daggers closer. It seemed she was not willing to take any chances.

Zuko glared at the man. "I'm going to remove my hand. Do anything to call for help and I'll kill you."

Which was a bluff. Not that the captain needed to know that.

Zuko removed his hand and waited expectantly for an answer. The captain still tried to resist, but eventually he cracked enough to tell them that it was War Minister Qin and those who had been working on the drill who knew everything. He was just in charge of helping to transport the tanks."

"Drill?" Zuko repeated, latching onto the word.

The captain realised his mistake too late. He renewed his struggling and managed to shoot off a fireball. Zuko deflected the attack with ease and pinned him down. Katara pressed her sharpened ice daggers to his throat, taking over the role of interrogator. She was in a better position to do so anyway since her bending was the strongest while the moon was up.

"War Minister Qin," she said calmly. "Which boat is he on?"

The captain spat obscenities at them both. Katara put just enough pressure on the ice daggers to draw blood. Her expression was cold. "Don't make me ask again," she warned.

The captain swallowed, Adam's apple bobbing in his throat. Zuko couldn't blame him for being afraid. Even he wasn't sure if Katara was bluffing. There was a spark of darkness in her eyes that he had rarely seen. It was like something ruthless had been awakened inside her. Still, her scare tactics did the trick. The captain disclosed the information they wanted, albeit in a bitter voice. It seemed self-preservation had won out over loyalty.

Zuko bound and gagged him, then shifted his gaze to Katara. "You okay?"

He wasn't sure if she had ever interrogated someone before. Not like that in any case.

She nodded. There was no trace of darkness in her expression now. "I'm fine. Let's just hurry. We've got what we wanted here, right?"

He made a sound of agreement and headed with her back out the window. She sunk them into the sea in a bubble of air, then manipulated the water to carry them to War Minister Qin's ship. It was safer to move this way—safer for Appa as well, who had retreated some distance and waited to be summoned with the bison whistle that Katara had "borrowed". At last, they surfaced and waited until the coast was clear before climbing aboard.

"We should split up," Katara suggested. "We'll be able to work faster that way."

Zuko hesitated. It wasn't that he doubted her; she had well and truly proven herself capable. He just knew that if anything happened to her, Aang and Sokka would have his head. Still, she was right that they would be able to find the minister much faster if they separated.

"Alright," he agreed. "Just remember that it's likely Azula is on this ship. If you run into her, don't try to fight. Just get out quick."

"That goes for you too. Don't do anything reckless."

"I won't."

He knew things would turn ugly very quickly should he and his sister meet. That would only get in the way of the mission. Tonight, getting the invasion plans was the most important thing on his agenda. His sister could wait.

Katara told him to be careful once more and then the two parted ways. Zuko watched her retreating figure before he let out a breath and moved to his self-assigned area. Time to try this again.

oOo

Zuko knew he'd hit the jackpot when he came across the fancier cabin rooms. He scaled the metal walls, blending into the shadows to avoid the patrol guards when needed. Eventually, he found what he was looking for: an older man dressed in expensive Fire Nation robes instead of the typical decorated armour seen by higher ranked soldiers. War Minister Qin was a government official, after all. Zuko had only met him a few times, but he remembered that Qin had been in charge of the military's technology.

Carefully, Zuko pushed open the window and entered the room. He crept up behind the minister, wanting to catch him by surprise. Qin froze and sprang to his feet. Zuko realised too late that his image had been reflected on the mirror resting by Qin's hand. No time to be stealthy now. Zuko rushed ahead and grabbed Qin by the throat, but not before he managed to hit the gong to trigger the alarm. Something hollow opened up inside Zuko's stomach.

"What will you do now?" Qin asked. His words were brave, though he licked his lips nervously. The war minister had never been much of a fighter.

Zuko gritted his teeth. Shouts had already started up from outside the room, calling for the soldiers to gather to catch the intruder. Bells clanged. Judging from the jarring rhythm, it sounded like the other ships had picked up on the alarm. Zuko hoped Katara was okay.

"I suggest you release me now," Qin advised. "They will come for you soon."

Zuko's eyes narrowed. "I hear you're the one to talk to about the drill." He tightened his grip on Qin's throat. "Tell me, what exactly is it?"

Qin's eyes darted to the side. An involuntary flicker.

Zuko followed his gaze and saw scrolls spread out on the desk. It looked like blueprints of some kind. A faint smile curved his mouth. "I see," he said softly.

He manoeuvred Qin backwards and snatched up the scrolls. One glance at the diagram had his eyes widening.

"What the hell is this?" Zuko demanded, rounding on him. "Is Azula planning to use this machine to break through the Outer Wall?" His voice roughened to a more threatening tone. "You helped to design this thing, right? What's its weakness?"

Qin swallowed. The shouts and sound of footsteps were getting louder from outside the room. Something thudded against the door.

The corners of Qin's mouth twitched. "It's too late for you. Even with those schematics in your hand, you will not be able to stop the drill. It is the perfect machine."

Zuko cursed and released him. He ran for the window just as the door was knocked off its hinges and several elite firebenders burst through the entrance. Flames rushed for him. He dived through the open window, feeling the heat of his opponents' attack sweep against the soles of his boots. That had been too close.

Still in freefall, Zuko latched onto the metal grooves of the ship with his free hand, abruptly halting his descent. He stuffed the scrolls into his tunic and started climbing. Much as it would be easier to just fall into the ocean, the drop was massive and he did not have a waterbender to help cushion his fall. For now, all he could do was try get to a better vantage point so he could find Katara.

"The intruder is getting away!"

That was Qin again. No sound of nerves in his voice now. Zuko would have snorted in amusement had his situation not been so dire. Fireballs were still being shot at him, and some of the soldiers had started scrambling after him in pursuit. Damn it, these bastards were persistent. Still, not for nothing had he trained as the Blue Spirit. He'd lose them yet.

Zuko quickened his pace, focussing only on finding the next foothold. Something flickered out the corner of his eye. He ducked—too late. Sharp metal grazed his cheek, tearing apart the cloth mask that had been hiding his face. He glanced up in the direction from where the projectile had come. A girl stood on the balcony he had been about to climb. Her black hair was unbound and she was wearing a loose robe, but there was no mistaking her features. She would always be familiar to him.

"Mai."

The name was wrenched out of him, almost like a punch to the gut that knocked the air from his lungs. He had run into her once when he'd had amnesia, but it was different this time. This time, he could look into her eyes and remember the quiet girl who had used to read scrolls under the cherry tree at the palace. He remembered her dry wit and even that embarrassing day he had knocked them both into the pond when he had tried to save her from Azula's antics. She had been a sort of friend to him back then, more so than many of his other childhood acquaintances. It was surreal that he confronted her now as an enemy. Surreal and sad.

Mai stood motionless, razor blades rimming her knuckles in preparation to strike. His pulse quickened. If she attacked him now, he would undoubtedly fall and be captured.

"You really are stupid," she said.

Her voice was flat, almost emotionless. She didn't attack him, though. Not even when the fog rose up from the waves and passed over the boat, blanketing everything in a thick cloak of white. A hand closed around his wrist. Katara's. Suddenly, he was being lifted into the air and pulled onto Appa's saddle. When he glanced back at the balcony, any trace of Mai had gone.

Katara grinned at him. "Aren't you glad I came with you now?"

Zuko made a noncommittal noise. It was true that Katara had rescued him. Thanks to her little fog trick, they'd also been able to escape with the drill blueprints. Still, he found that he couldn't find the energy to celebrate. Not really. His heart felt too heavy and unsettled.

A name hovered on his lips, though he didn't speak it aloud. All he knew was that another girl had saved him in her own way tonight. Mai had let him escape. It was something he could not forget.