I got this idea after reading a doujin where Ed was a merman that became human to be with Roy but when he became a human he just straight up came out with it and told Roy that was what he was there for so I decided to write a story and also one that retcons the huge plot hole in The Little Mermaid (you know where Ariel can read and write English!) Anyway hope you enjoy this first chapter :)

Once upon a time deep down in the depths of the ocean, so deep you and I can only dream about it, live the merpeople. Half fish, half human the merpeople live beneath the waves spending their days just as we would on land, under the care and supervision of their ruler King Hohenheim of the Seven Seas.

Now King Hohenheim had two sons, both bright, inquisitive boys; Edward and Alphonse. Alphonse was the younger; he was timid and a little shy and often went along with Edward trying to make sure that he didn't get into too much trouble. Edward was two years older and, by the time he reached the age of sixteen, he had become fascinated with the thing his father despised the most; the world above the waves.

More than anything Ed wanted to know what life was like on land. He would go up to the surface whenever he got the chance and always received a very stern telling off from his father once he returned. He would learn everything he could about human culture in whatever way he could and he loved to explore sunken ships in the hope of finding some human trinkets he could add to his ever growing collection.

And it is in one sunken ship which our story begins...

"This place is amazing!" Ed gasped as he swam down the corridors that had once been beautiful but were now a shadow of their former glory. Gilded banisters and ornate floors now rotten and decaying from so many years under water. "How did you find it?"

"Lan Fan told me about it when she came out this way with Old Man Fu the other week," Ling said following behind.

Ling had been a friend to Ed and Al since they were children. He was brash and abrasive and liked to tease Al a lot but he was also very loyal and willing to find sunken ships for the three of them to explore.

"Guys," Al called from where he was brining up the rear. "I don't like this place, it gives me the creeps."

"Well you'd better keep up then," Ling said smirking over his shoulder at him. Al blushed and picked up speed.

Out in front Ed stopped at a door and wiped some of the accumulated grime and algae off to reveal a golden insignia underneath.

"White Star Line," he read. "What is White Star Line?"

"No idea," Ling said. "Maybe it's the name of the boat."

"Nah that was on the back of the ship," Ed said.

"Guys can we go?" Al asked nervously. "What if we run into a dead body or something?"

"Al you're such a guppy," Ed said shaking his head. "Anyone who went down with this ship is long dead by now. The worst we're going to find will be maybe a skeleton."

"Oh god!" Al squeaked and grabbed onto Ling's shoulders, burying his face into his back and squeezing his eyes shut.

"Get off!" Ling said giving him a harsh shake. Al hugged himself and looked down at the floor.

"Al if you're really nervous then why don't you go back up to the entrance and watch for sharks," Ed said, "or Dad," he added as an after thought. Al's eyes widened a the thought of being left alone anywhere near this sunken ship on his own.

"No it's okay," he said. "I... I'll come with you."

"Then you're going to have to keep up," Ed said grinning at him before swimming off. Ling followed suit and Al just stared after them for a second longer than he should have.

"Hey wait for me!" he cried as he tore off down the corridor behind them, trying desperately to catch up.

"This place is incredible," Ed said as he pushed a door that was falling off its hinges open and swam into the room inside. "I mean can you imagine what it must have looked like when it was brand new?"

"Big," Ling said. "This is only half the ship, I have no idea where the other half is. Could be miles away."

"W... what if this place is haunted?" Al asked nervously as Ed swam over to a chest of draws and began rummaging through the top draw.

"It might be," Ling said smirking. "All those souls lost to the sea looking for an unsuspecting young merman to possess so that they can live the life that was taken from them." As he spoke he swam up behind Al and grabbed his shoulders. Al jumped, crying out loudly as he did, and Ling burst into fits of laughter.

"That's not funny Ling!" Al snapped, glaring at him through indignant tears.

"Your face!" Ling laughed. "You actually thought I was a ghost come to get you."

"Well I'm sorry I'm a little on edge, this place is creepy!"

"You're such a guppy," Ling said as he fought to catch his breath, holding his stomach he was laughing so much.

"I am not!"

"Oh my god!" Ed cried excitedly. Both Al and Ling jumped (Al letting out a shriek too) and turned to look at him, having momentarily forgotten he was even there.

"What is it?" Ling asked as they both swam over to him.

"Look at this," Ed replied holding up what had once been a small, ornate comb. There were a few of the teeth missing, the paint had faded and the butterfly on the top only had one wing. Al clutched his chest and sighed.

"God I thought it was something important," he said.

"This is important," Ed said. "Look at it."

"It's cool," Ling said. "What is it?"

"It's a comb," Ed replied.

"Okay... what's that?" Ling asked.

"Humans use these to make their hair look nice," Ed said and ran the comb once through his long blonde hair.

"Is it supposed to have more of these prongy things?" Ling asked giving one of the teeth a gentle flick.

"I think so," Ed said. "I imagine it was really pretty when it was first made but isn't it amazing! Humans use these things every single day on the surface to make themselves look nice and it's just so cool because they don't even think about it."

"If you want to start doing things with your hair I'm sure we can arrange that," Ling said rolling his eyes. Ed was about to go off on one again, he could tell but he didn't have the heart to say anything. Ed gushing about the human world was what made Ed, Ed.

"Oh I just want to go up there and see if for myself," Ed said. "I'll bet it's amazing and humans just go about their daily lives up there without even thinking about it of the fact that there's an entire world down here beneath the sea."

"Well no but I'm pretty sure any human who said they believed in merpeople would get put under some kind of observation," Ling said. "Is there anything else in there?" he asked, changing the subject before Ed decided to go to the surface and get them all in real trouble again.

"Hopefully," Ed said as he began to search through the next draw down, wading through the mulch from years of being at the bottom of the ocean until he found something solid. His fingers closed around it and he pulled it out.

"What is that?" Ling asked as Ed pulled out a small, but very ornate smoking pipe.

"I'm not totally sure," Ed replied, "but from what I've seen in books my guess is that it's a very small musical instrument that if you play it too fast smoke starts coming out."

"That's stupid," Ling said.

"I think it's awesome," Ed replied. He put the pipe and the comb in a small pouch tied around his waist and continued his search for more treasures.

Meanwhile Al had swam over to the huge window that covered one entire wall of the room. He looked out into the vast ocean trying to spot anything that might be moving towards them, or anything that might be lurking around in the darkness, and hoping that Ed would hurry up and get bored of exploring so that they could leave before something happened.

Al did not share his brother's fascination with the human world. In fact he found the human world and the prospect of life above the waves quite scary and he had no desire to see what was up there. Humans were weird with their two legs and their lack of being able to breathe underwater and, if the stories their father had always told them were true, then humans ate fish and would probably eat merpeople given half the chance.

As Al stared out into the blackness, letting the chatter from Ed and Ling from behind wash over him. That was until he thought he saw something moving towards them through the inky black depths.

"Um guys I think we should go soon," he said. Were his eyes playing tricks on him or did he actually just see something moving out there in the water.

"Yeah, yeah just a second," Ed said.

Al sighed before turning back to strain his eyes against the darkness until he saw it again. Whatever it was it had suddenly gotten bigger and he realised that it was, in fact, moving towards them and they should probably leave.

"Um guys..." he said.

"For goodness sake Al what is it?" Ed snapped as he and Ling swam over to the window, one either side of Al.

"I saw something moving out there," Al said pointing out into the dark expanse of water before them.

"It's probably just a fish," Ed said sighing. He really needed to stop bringing Al when he and Ling went exploring. Al was too nervous about everything that moved and always tried to drag him away as he was finding something good.

"It was bigger than a fish," Al said.

"Then it's probably a dolphin or something," Ed said. "Will you relax?!"

"I don't think that's a fish or a dolphin," Ling said as the shape suddenly began to pick up speed as it swam towards them.

The shape swam through a patch of light revealing it to be a huge shark, ready and waiting to grab its prey and what a prey it was – three young, unsuspecting mermen just ripe for the chomping.

Ed, Ling and Al all screamed and frantically swam back the way they had come as fast as their fins could carry them. Despite teasing Al about being a guppy sharks were a big no no in Ed's book and his fear of being eaten alive was much stronger than his desire to explore and collect human trinkets.

They finally reached the small gap they had come in through and left the remains of the ship only to be cornered by the shark as it cleared the ship to appear in front of them, having not had to negotiate corridors. The simple solution under these circumstances would be to swim upwards and not stop swimming until they reached the surface but there was nowhere for them to go after that. They weren't near land so they had no means of escape.

The shark advanced on them, moving a lot slower now that it knew it had them cornered. Slowly, as if mocking them, it opened its huge mouth to reveal two sets of huge, sharp teeth. Ed closed his eyes, not really wanting to look into the actual jaws of death for longer than he had to, and waited. Suddenly there was a very loud crackling sound.

Ed opened his eyes to see a flash of electric blue light. It shot through the water and hit the shark square in the side of the head and sent it careening off in the other direction. He turned towards the direction the light had come from as the shark swam away and his heart sank as he saw a powerful looking merman, his hair floating around his head on the water like a terrifying golden crown, glaring at the three of them, his trident pointed in the direction the shark had turned tail and fled.

"Dad!" Al cried happily and swam over to their father.

"Would one of you care to explain what you are doing out here when you should be at home engrossed in your studies?" King Hohenheim of the Seven Seas asked.

"Oh great..." Ed muttered looking down at the floor and trying to work out just how much trouble he was going to be in. He guessed that it was going to be a lot.