A couple of hours before sunrise, Appa took off for the Fire Nation Palace, fur carefully darkened with charcoal. It wasn't all that easy finding their way in the dark, but the gibbous moon dancing in and out of the clouds helped. When they got closer, the torches decorating the palace helped, too.
They dropped Toph near the entrance. Then the rest of them set off for the Central Tower. This was hard to miss, being by far the tallest point on the palace.
Appa landed awkwardly on the sloping roof, nearly sliding off before he found purchase. It creaked under him.
Aang darted off, over the side of the roof, and up to the nearest window. There was no light from inside, and it refused to open to his questing fingers. Locked. Aang pulled an airblast through the top left of the window, shattering it and pulling the shards out over his head. He heard a window breaking over the other side as he opened his own window and darted inside. "Zuko!" he whisper-shouted. "Zuko, where are you?" Katara climbed in through the window behind him.
There wasn't any response. It was dark enough inside that he lit a flame in the palm of his hand, which showed... an empty bedroom. No Zuko. A little flame flickered in the corner of Aang's vision, and he turned slightly to see Iroh looking through the broken window on the other side, a grim look on his face.
"Aang, don't move," he said. "Zuko's gone, so we need to assume this place may be trapped."
Aang froze, and he could hear Katara's quick intake of breath behind him. He couldn't see anything that looked like a trap, but if it was anything like what the Sun Warriors had come up with, this could be really bad. At least there weren't any giant gold egg-things here for Iroh to get fascinated by and get them both stuck in black goo.
Iroh enlarged his flame, and suggested Aang do likewise.
"I don't see any traps, do you?" said Katara. "Are you sure this is the right place?"
"It was." Iroh leaned awkwardly through the shattered window, and pointed at a bit of fluff on the floor. "That looks like a feather off his catowl kitten. He was here, but he isn't now. They probably moved him very recently, or this wouldn' t be here and Qin would have thought to trap the tower."
They could hear footsteps coming up the stairs. "Monkeyfeathers," said Aang.
"We need to get out of here," said Iroh, removing his head from the window. "Time for the backup plan."
Aang darted out his own window, followed rapidly by Katara.
Shouts rang out from underneath when Appa took off, and part of the roof crumpled into the room below as a roof support gave way.
Toph was easy to find. She was standing on a stone pillar demanding loudly that the guards let her see Zuko. The guards were running aroung the maze full of stone statues she'd turned that part of the main entrance to the palace into, looking bewildered.
"Have you got him?" yelled Toph, as Aang set Appa down carefully in an Appa-sized clear zone Toph thoughtfully created for them.
"He wasn't there," said Aang.
Iroh slid down Appa's tail. Toph ran to them, and Iroh grabbed her hand, then looked around. "Toph, if you wouldn't mind putting the stonework back the way you found it?"
"Fine," said Toph. "Spoilsport." She made a couple of gestures and stomped her foot three times. The statues, maze walls and stone pillar disappeared as the pavement smoothed itself back out.
"General Iroh?" asked one of the guards. "What are you doing?"
"Looking for my nephew. I'd heard he'd been kidnapped and held prisoner in that tower." Iroh pointed. "And now he seems to be missing entirely. Do you know where he is? Is he all right?"
"Errr..." said the guard. "That's the Avatar, isn't it?" he pointed at Aang.
The guard behind him facepalmed. "Yes, that's the Avatar, and the Fire Lord's traitor uncle," she said. "Straight from trying to kidnap the Fire Lord. For Agni's sake don't tell them anything."
"I'm not kidnapping anybody, and the Avatar is here to talk to Qin and investigate the Dai li plot. Katara is a healer, and is here to help my nephew." He turned to Toph. "Toph, let's go." She nodded, and earthbent them both through the floor, leaving Aang and Katara behind.
Aang was frustrated and trying not to fidget as they sat on the short stone rounds he'd created in the middle of the courtyard. Oh, the servant had tried to show them to a nice private room to wait, but Katara had insisted they stay out in the open where no one could sneak up on them, so Aang had made chairs. They were sort of basic, but oh well. Toph could laugh at him when she returned. It wasn't like he'd had time to master artisanal earthbending while learning to defeat Ozai.
The servant still waited a few feet away, playing statue and watching them. About ten feet away, Appa was busily demolishing a pile of hay. Tea and biscuits were served. Katara and Aang did not pick them up. However, no one had told Momo. The lemur grabbed a cookie and looked up at Aang.
"No!" cried Aang, lunging for Momo. Momo shrieked, and flew off to Appa's saddle. Aang airscooted after him, and managed to pry most of the cookie out of his hand. Not before Momo had taken a bite, though. Momo chittered angrily and flattened his ears at Aang, who jumped back to the ground holding him.
He traded glances with Katara as he walked back to the little circle of earthbend um... things, and sat down next to Katara. Toph really was going to laugh when she sensed them. Hopefully Qin hadn't poisoned the cookie, or it wasn't something that would hurt a lemur.
"Are cookies not food for lemurs, then?" asked their watcher.
"Uh, Momo's on a diet. He's not to eat cookies right now, only natural foods."
Momo made sad eyes at him.
"Oh stop it, Momo, it's for your own good," Katara. She pointed a finger at him, and he sniffed it. Katara glared at the lemur, but continued talking. "Doctor's orders. You know you're not supposed to eat this. Bad lemur."
"What do lemurs eat?" asked the servant.
"Bugs and fruit, mostly," said Aang. "But they'll eat anything, even if it's not good for them."
"I can get some fruit for you, if you'd like," offered the servant. "We don't normally stock insects. I suppose the hawkmaster might have something like that..."
"It's okay. Momo normally catches his own bugs anyway. He likes to chase them."
The sun crept over the horizon. Someone came and began firebending all the torches out. Momo went to sleep on Katara's lap. They exchanged glances again. Natural sleep or not? Who knew?