The air was cool, gray, and slightly breezy. A thick fog had rolled over hours before, covering the horizon with its mystery. The ocean was alive and breathing, waves tumbling over the water's surface, white foam rising over the crests.

It was a fine day for sailing.

Toucan-puffins were catching the wind beneath their wings, floating down from the sky. A pair of tiger-dolphins poked their heads up out of the water, leaping over the waves. The birds flew down towards the ocean, dipping precariously close to the surface. The tiger-dolphins greeted the birds with a high-pitched giggle, and sea spray glided smoothly off the toucan-puffins' feathers. They soared up high again, high above it all.

The figurehead of a mermaid with carved wooden hair fluttering behind her and hollow eyes, deep and heavy, broke through the fog, revealing the bow of a great and powerful ship hidden in the mists, the ship of the princess returning home after a long and grueling journey in the northern seas. The Northern Air Temple had been left behind in its wake.

The ship's crew worked the riggings, capturing the wind in the sails, and they sang, voices booming.

"I'll tell you a tale of tale of the bottomless blue,

"And it's hey to the starboard, heave ho-"

Korra was standing in the crow's nest, eyes closed. The wind flitted through her hair, ruffled her loose, white shirt, and she breathed in the day, crisp, clean. Up here, she could forget her disappointment, forget the feelings of failure that had followed her from the temple. She gripped the wood in front of her, and she felt the air on her skin. Her eyes opened, taking in the horizon, her home.

She was a sailor, and sailing made her free.

"Look out, lad, a mermaid be waiting for you,

"In mysterious fathoms below."

Korra climbed up onto the edge of the crow's nest and reached out, grabbing onto some cordage. She leapt off, making sure not to get tangled in the rigging before arcing out over the ocean. The singing halted in an instant; her crew stared up at her with huge eyes, and she laughed to the sky as she swung back over her ship, inhaling the salty air and the smell of the sea.

She let go and somersaulted onto the deck.

One of her crew members, those members of the Order of the White Lotus who had sworn to protect both her and her ship, ran over to her, worry still stricken across his face.

"Are you okay, Princess Korra?" He reached down to help her up. "You had me worried."

Korra rolled her eyes up at him, and gently pushed his hands aside so she could stand on her own. "I'm fine, Howl. No need to worry." She stared back up at the billowing sails as she adjusted the red sash tied around her waist. It kept loosening on her. "It's a perfect day to be at sea, isn't it?"

Howl followed the princess to the port side of the ship, where she grabbed onto the rigging again. His voice was low. "A strong wind and a following sea. Our journey back couldn't be better. Queen Lin must be in a good mood today."

"Queen Lin?" she asked, eyebrows raised.

Another crewmember leaned over. "She's the ruler of the merpeople, miss. I thought you of all people would have known about her."

Korra crossed her arms and pouted. She grumbled underneath her breath. "Well, maybe I would if I was allowed out of the city more often instead of only being allowed to leave for Avatar duties. I barely was allowed to go to the Northern Air Temple; whose fault is that, huh?"

"Korra?" an old woman called from the stern. Korra glanced up and saw her oldest and closest teacher, looking slightly green, beckoning her over. She ran up to her.

"Yes, Master Katara?"

"I know you're disappointed that you didn't learn anything new about airbending on this trip, but there is no need to take it out on your crew." Korra groaned, and Katara continued, "I promise you, one day all the practice you've been doing and all the time you've put into training will pay off, and everything will just click."

"But you've been saying that for months now!"

"And it's still true."

Korra turned, eyes downcast. She held her hand over the edge of the ship, bending a stream of water up and down. A bubble of water rose up from the sea, and the tail of a skunk fish flicked around, threatening to break the surface tension.

"Katara? Do you believe what the crew was saying? That there are really merpeople? A queen of the seas?"

Katara rested a hand on Princess Korra's shoulder. "I've been on many adventures in my lifetime, my dear. And frankly, I wouldn't believe that kind of nautical nonsense."

"Yeah, you're probably right," she said, just as a gust of wind burst across the ship. Her red sash unwrapped and flew out over the ocean. The water bubble she'd been maintaining broke as she tried to waterbend her sash back, but the ship was going too fast by that point. It floated away, dipping below the waves before she could jump in after it.

The fish she had dropped looked back up once, and swam away before she could get him again.

The sash absorbed the water and sank.

Her crew began to sing.

"Heave, ho. Heave, ho. In mysterious fathoms below."

Deep beneath the ocean's waves, the water was dark but warm. Crowds of merfolk were swimming towards the palace, fins flipping behind them with an anxious excitement. They'd been planning on attending for weeks now, talking about it nonstop ever since they heard rumors of a surprise guest.

Inside the underwater concert hall, the crowd was overwhelmingly huge. Families of merfolk waited patiently, a buzz of conversation echoing throughout. A fanfare began, silencing the crowd.

A tiny seahorse swam out next to the trumpeters, and coughed. Her voice was small, but she projected well. "Ahem..." she began, "Her Royal Highness, Queen Lin!"

The queen rode out into the middle of the hall, pulled in her half-shell by three tiger-dolphins, holding her glowing trident up high. She was a respected queen, a revered and loved queen, and the explosion of applause that rang out when she appeared burst through to the furthest rooms of the palace.

"Thank you, Pema," she said kindly as she rode past the seahorse.

"Not a problem, your majesty."

Queen Lin soared over the audience, the tips of her dark gray fin flitting over the edge of the shell. Her hair moved with the water as she rode. She pointed her trident towards the ceiling, and a cascade of sparkles rained down to even more applause. She settled in a spot where she could easily view the show.

Pema spoke again, blushing slightly: "And presenting the distinguished court composer, Horatio Thelonious Ignatius Crustaceous Tenzin!"

A small, red crab with blue arrows running down his back, claws, and head swam out to little applause and moved towards the queen.

"You're looking radiant today, my queen," Tenzin said as he approached Queen Lin.

She ignored his compliment. "I'm really looking forward to this performance, you know."

"Oh, your Majesty, this will be the finest performance I've ever worked on. Your sons are magnificent!"

"Yes, they are, aren't they? Especially my Mako." The pride in her voice was unmistakeable.

Tenzin nodded furiously, clicking his pincers together. Bubbles rose up from each snap of his claws. "He does have a wonderful voice, your Majesty," he said as he swam down to the podium set up in the middle of the hall. "If only he came to rehearsal!"

The crowd was silent, waiting.

Tenzin tapped his baton on his music stand twice. His musicians, an octopus and seven fish, stared up at him expectantly. He started to wave the baton furiously as he conducted the instruments, and the sounds of music, of trumpets and trombones and drums, filled the hall. Queen Lin smiled.

Three shells rose up before them, supported by coral-covered rocks. A curtain of bubbles hid them, and with one flick of his claw, Tenzin bent them away. The middle shell opened, revealing two mermen, and the other two shells opened shortly after.

"Ah, we are the dear sons of Queen Lin-"

Her sons were metalbenders, and as they sang, they directed their hands below them to shift the earth into patterns. Their voices were deep, harmonious, and their bending powerful. They'd learned from the best.

"Great mother who loves us and named us well-"

Lin looked proud, even behind her crossed arms.

"Saikhan, aaah-aha,"

"Kaelin, ah-aha,"

"So-ong, aah-ha-ha,"

"Ke-ehn, ah-haha,"

"Shui, aaah-ahah,"

"Kohei, aaa-aa-a!"

Tenzin grinned, lifting himself up in the water with his legs as the brothers hit the highest note. The six of them swam together, a blend of greens and yellows and browns and grays from their fins as they formed a circle. A fourth shell rose up, spinning, the mystery hidden inside, the surprise the crowd had been waiting for.

"And then there is the youngest in his musical debut,

"Our seventh little brother, we're presenting him to you-"

They swam towards the shell, arms outstretched, waving, bending, giving their all in this performance. Tenzin looked back to make sure Queen Lin was watching.

"To sing a song that Tenzin wrote,

"The brightest of our show-"

The shell began to open slowly.

"He's our brother, Ma-a-"

A gasp tore through the crowd.

...The shell was empty.

Lin gripped the bannister, face tight with anger. The coral broke easily with the force of her bending, and her yell echoed throughout the hall.

"MAKOOOO!"

Mako floated up in the water, staring at the sunken ship that he'd heard so many rumors about. He smiled, gloved hands resting on the rock in front of him. "Wow," he murmured before swimming forward. His deep red fin twirled once before it propelled him forward.

"Mako!" Bolin called from behind. "Wait for me!"

Mako turned, the water flowing between his fingers as he stopped himself and looked back at his friend, a yellow tang with green stripes and fins, though his dorsal fin was, oddly, colored black. A little red and orange pentapus was sticking onto his side, riding along happily. "Hurry up, Bo!"

"You know I can't swim that fast," he said, panting as he caught up, "I'm not as speedy as you, okay?"

Mako ignored him, mostly because he couldn't take his mind off the sunken ship. What was hidden inside? What kinds of treasures were waiting for him? He felt the jolt of excitement in his fingers; he still hadn't been able to shake the desire to treasure hunt, even after all the years that he'd been living as Queen Lin's adopted son.

He often forgot that he was a prince.

He still thought of himself as a thief, as a hunter, as a kid just trying to make it.

As a young merchild, far too young, Mako had lost his parents and had to find a way to survive on his own. He stole a lot. He slept on beds of seaweed, deep in the reef. One day, he'd found a human treasure in the seaweed, and soon discovered that human things went for big money on the black sea market. He hunted and he stole and he survived.

He used to get in fights with other benders, too. He still had the scars beneath his gloves. And once, during a huge fight, he was arrested by one of the Queen's sons. He'd brought him back to the palace, and instead of getting into trouble, the Queen ended up taking a liking to him. He impressed her, and a year later, she'd adopted him as her own.

He loved his mother.

But he loved human treasures too, and though he had no need to find them for monetary purposes, they still sparked his curiosity.

"Isn't it great?" Mako said, voice hushed even though he knew they were the only ones around.

"Yeah... it's great... now can we go?" Bolin asked nervously.

Mako rolled his eyes over at him. "Please don't tell me you're getting cold fins. Focus, Bolin."

"Of course not!" Bolin waved himself around. "It's just... I think I'm getting sick. Yeah, I'm getting sick, and besides, that looks pretty... um... wet in there. Very moist indeed."

"Well I'm going in. Never know what I could find. You can just stay out here and watch for sharks!" He adjusted the bag on his shoulder and swam away, swishing his fin in Bolin's face.

"Sh-sharks? No way. There aren't really sharks here, nope. I don't see any elephant-sharks or any jaguar-sharks or any hippo-sharks. Yeah, no sharks here!" But he followed behind Mako anyway, avoiding his current to swim at his side.

"You're such a guppy, Bo."

"I am not a guppy!" Bolin shouted as they squeezed through the ship's porthole. "Am I a guppy, Pabu?"

The pentapus lifted a tentacle off Bolin and tapped it down twice before leaping off and sticking to Mako's shoulder.

Bolin groaned. "Pabu, you're supposed to be on my side."

Mako laughed. "Don't worry, I'll protect the both of you." Mako peered through the ship, but he couldn't see anything.

"I'm an earthbender, remember?" Bolin bopped over to Mako. "I don't need protection... but... it is a little... dark in here. Could you... you know...bend?" Bolin had, by this time, stuck himself to Mako's side. He was shaking.

Mako raised his hand in front of him, and felt the anticipatory tingles running through him. His fingers lit up, little shivers of electricity dancing over his hand. He held it up, illuminating the ship's dark insides. The water started warming.

Something reflected the bluish glow and caught Mako's attention. He swam closer, holding his electrified hand down to the ship's floor.

Human treasure.

It had to be!

He picked it and examined it. It was some type of metal, thin and flat and pointy, but only pointy on one end. It kind of reminded him of a kangaroo-urchin. "Isn't this the coolest thing you've ever seen?" he asked, grinning at Bolin.

"It's gorgeous! ... What is it?"

"I have no idea," Mako said, shrugging; he placed the object in his bag. "But maybe Jinora will know!" Another thingamabob caught his attention, and he shoved it in his bag without even examining it.

Bolin's smile dropped off his face. "Did you hear that?"

Mako's attention had already been drawn to the red fabric dangling off the stairs leading up to the poop deck. The electricity left his fingers as he reached for it with both hands. It was soft.

"I wonder what this is," he said as he held it to his face, rubbing it over his cheeks.

"Mako, I am really getting the heeby-jeebies here..."

"Stop it, Bo," he said as he pushed the fabric into his bag. "Nothing bad is going to happen."

A crash of splintering wood echoed through the ship, and Mako whipped around.

A shark had burst through, snapping his jaws at them.

"WE'RE GONNA DIE!" Bolin screeched as the shark burst through and chomped at him, nearly nipping his caudal fin. Mako grabbed Bolin and swam, hoping that Pabu was going to stick to his skin.

His bag yanked out of his arm as he dodged the shark, zooming behind a mast. He couldn't leave it. He couldn't. So Mako swam up and then whipped back down, fin snapping as he reached down for his bag. The shark approached, mouth open, teeth sharp. Mako's fist thrust out, and the shark was jolted with a shock of electricity. The surrounding water bubbled with the residual heat. The shark shook his head, giving Mako enough time to bolt back towards Bolin, and the two fled the ship.

"Bad shark coming, bad shark coming, BAD SHARK HERE! NOW!" Bolin screamed behind him. Mako glanced back, and sure enough, the shark was still after them, even after getting shocked.

He needed a plan.

His eyes darted around until he noticed a huge, rusted metal ring. He swam towards it; twisting through the ring's center without any problem. Bolin, however, swam right into the metal, conking his head. He spun, sinking as he tried to reorient himself, but the shark was coming, his jaw's were wide and his teeth were huge. Mako spun back, flipping his fin, and grabbed Bolin, pulling him through the ring's center.

The shark snapped his teeth and wiggled his fin, but was very, very stuck.

Pabu's tentacles trembled in relief on Mako's skin, and Bolin rolled out of Mako's grasp, swimming over to the shark.

"You are one nasty dude!" he said, sticking out his tongue.

Another attempted chomp sent Bolin screaming back into Mako's arms.

"You really are a guppy," Mako said, laughing.

Three seagulls hopped around on a rock at the surface, one of them humming. Another of them hopped to the edge of the rock, fluttering its wings as he lifted his telescope. He peered through it on the opposite way, observing the horizon.

"Jinora! Ikki! Meelo!" Mako called.

Meelo turned, still looking through his telescope the wrong way, and saw Mako waving in the distance, Bolin was bobbing in of the water. Pabu had stuck himself on Bolin's side once more. "Whoa! Merman entering my domain!" he shouted.

"Meelo," Jinora said, "There's no need to yell."

Meelo lowered his telescope, and jumped back. Mako was right next to him; he tossed his bag up onto the rock. "Hey, you three, look what we found!"

Bolin did a flip in the water. "We got it from this super creepy ship! It was super creepy."

Ikki flew over to the bag, reaching inside. "Human stuff? Let me see." She reached inside, pulling out the flat piece of metal.

"Ooh," Jinora breathed. "That's special. Very special."

"What is it?" Mako asked, leaning closer on the rock.

"It's a dinglehopper!" she said, taking it from Ikki and pushing the spiny ends onto her sister's head, swirling it around. "Humans use these to fix their hair. You just give a twist here, a tug there, and voila!" She yanked the dinglehopper away, leaving Ikki's feathers fluffy and puffy.

"Oh, very nice," Ikki said, wings reaching up to touch the top of her head.

"It's quite aesthetically pleasing," Meelo chimed in.

"A dinglehopper," Mako repeated to himself.

Ikki continued digging through the bag, pulling out the red fabric and throwing it at Jinora, who ran her wings over the material.

"This," she said, hopping over to Mako, "Is a scarf. Humans use it to kill other humans by choking them!" She wrapped the scarf around his neck. "Just like this, but tight!" It didn't feel bad to Mako, though. It felt right. He liked the color, too.

"But what about this?" Bolin asked, nudging the last thingamabob towards Meelo.

"That, my friends, is a snarfblat," Jinora said. The other four made appropriate sounds of awe. "It's an object that dates back to prehistoric times, when all humans did was sit around staring at each other."

"Booooring," Ikki said.

"So they invented the snarfblat in order to entertain one another with fine music." Meelo picked it up and put it in his beak. He took a huge breath and blew out, bubbles exploding out the end.

"Music? Oh, no, the concert!" Mako cried, slapping his forehead with a gloved hand. "My mother is going to kill me. I have to go, now!" He threw the dinglehopper and the snarfblat back into his bag. "I'm sorry." He dove down, fin splashing up out of the water as he submerged, Bolin following. He swam as fast as he could, scarf trailing behind him, not focused on anything but getting back as soon as possible.

He was so focused on his thoughts, he didn't see them.

He didn't see the moray eels' two glowing green eyes.

He didn't see them seeing him.

"Hurry home, little prince." A smooth, deep voice resounded. His hands touched his crystal ball, his eyes watched Mako swim deeper and deeper. "You wouldn't want to miss your dear mother's celebrations."

He swam away from the crystal ball, tentacles pulsing with the movement.

He chuckled behind his mask, and the sound echoed.

"I'll show them a celebration. One like they've never seen before. Lieutenant! Hiroshi!" he barked, addressing the eels. "You better keep an eye on our prince. He very well may be the key to Lin's undoing..."

He laughed.