"Hello there, your majesty." The voice sent chills down Zuko's spine. He hadn't even realized someone was behind them until the man's breath was at his neck.
Katara impressively kept her wits about her and put on a convincing insulted face.
"Excuse me?" she said. "My friend Rokka here is just a representative from the Southern Water Tribe. He's not a leader there." Before she had the chance to move forward, however, another man darted out from behind a corner and stood right at her back. Neither had drawn weapons, Zuko noted. Of course, if they were skilled firebenders, they hardly needed to.
"Your sister's looking for you," the man next to Zuko whispered. "Now, if you'll just come quietly with us, this doesn't have to get ugly."
Right, because walking right into Azula's death trap isn't ugly. He had a plan worked out in his head for how this would work. First, it was best to get their guards down by going along with them a little ways. Then he could find the perfect opening when their backs were turned, and…
…and Katara really didn't follow the same strategy. With a flick of her hand, she'd already thrown a small flame in their enemies' direction, causing them to jump back and ready themselves for a full-on battle. Katara readied a firebending stance herself, pausing just a moment to narrow her eyes at Zuko.
"A little help would be nice," she said.
A little subtlety would've been nice too. Zuko said nothing and readied an attack position as well, but couldn't shake the feeling that something was missing. Katara glared at him like he was the stupidest person ever born.
"You didn't bring any water with you?"
"Hey, I'm not used to having to carry anything to use my bending, all right?" he snapped back. "I mean, can you imagine having to carry a torch with you everywhere or hope you get lucky enough to be standing near a lantern when you firebend? How stupid would that be?"
"Then find some water, you idiot!"
Zuko looked desperately around him. At the end of the alleyway, he saw a small fountain. Perfect, he thought. Or rather, it would've been perfect if he could call the water from this far a distance. Cursing himself for his stupidity, Zuko ran towards the water source, with one of the men on his tail and the other fighting off Katara.
Their enemies were both firebenders, for sure. Zuko could feel the hot flames behind him, each barely missing an arm or a leg. His mind was a blur as he focused on nothing but running, nothing but getting within range of the water. At last, he reached out his hand and a large jet of water came towards him so fast, he had to sidestep it. It pummeled the guy chasing him and knocked him unconscious to the ground. An excellent start. He turned to see how Katara was faring and saw it wasn't nearly as well.
The other firebender had Katara pinned to the ground, his hand inches from her face. She turned her head this way and that to avoid him, but getting out of his grip proved impossible. And no matter how fast Zuko ran, he could not get there fast enough. He watched in horror as the flames erupted from the man's fingertips, flowing onto Katara's exposed skin. Her scream pierced Zuko's ears. He felt a moment of fear, then his body was overcome with rage. He ran forward, barely aware of his own actions. The water from the nearby fountain lept up and came alongside him, split, and hardened into a blade of ice in each hand. He thrust the weapons forward, catching the man off-guard.
He jumped back, barely missing being wounded on the arm. Katara, still gasping in pain, had enough of her wits about her to roll away from danger. Covering the injured side of her face with one hand, she threw a line of fire in the man's direction. Now outnumbered, he threw up his hands in surrender, and disappeared down the road.
Zuko's first intuition was to follow him, hunt him down and make him pay for the pain he'd caused. Then he heard Katara's voice, quiet, whimpering. She knelt down on the road, clutching her face and leaning over. Zuko ran to her side. Even with her fingers hiding most of the injury, he could tell it was bad. Gingerly, he tried to pull her hand aside.
"It... it hurts," Katara whispered.
"I know," Zuko said. "I know, but I need to see it."
Reluctantly, Katara moved her arm and Zuko saw her face in full view. Her right eye was swollen shut, the skin around it red and raw from the burn. The sight brought far too many memories to his mind. He heard his 13-year-old self crying for mercy and getting none of it. Instantly, the cold dagger in his hands melted into an orb of floating water. It rested on Katara's face and began to glow. Zuko concentrated all his energy into healing the injury. He could see the skin starting to heal, but only lightly. This wasn't working. Not as well as he needed it to. A bead of sweat dripped down Zuko's face as he concentrated harder. He had to heal her. He couldn't let it scar. Not Katara's beautiful face. He would restore it, even if it took hours, even if he had to spend all the energy he had.