A/N: I suppose this is one of those "Lucy, you have some 'splaining to do" times. Yes, hello there, it's me again. With another fanfiction. Yay! It being summer now for me, I'm finally able to pick up my pen (or, I guess my laptop, since I type this stuff) and write once more. So I'm back with another classic multi-fic. I hope you enjoy it. Once again I'll be posting once a week (on a Monday or something).

Rating: K+ (For the moment. May switch it to T later if it calls for it, but you never know what mermaids will be like)

Pairing: Arwen (Arthur x Gwen)

Plot: A trade issue finds Arthur and Merlin in a small fishing village on the sea. But wherever these two go, trouble follows. Several fishermen have gone missing, and no bodies have been found. Merlin begins to suspect magic, and when Arthur, too, disappears, it becomes clear that he's right. But just how far is the warlock willing to go to free Arthur from the grips of beautiful sea women with a taste for human flesh?

Setting: Early series 4

Warning: Like before, I do not claim to own Merlin, it's characters, or its plots. This is a story inspired by the show, and all credit goes to the brilliant BBC writers who made this show, for however brief a time, a reality. Please enjoy.

Prologue-

"I can't believe this!" Maria screamed at her husband. Three months! Three months they'd been married, and already he was running around after some other woman! Three months and he was already turning a blind eye to her and sneaking out nightly to see this other girl in the tavern. Maria knew! She'd followed him and found him sitting at a table, the little wench in his arms, sitting on his lap, cooing over him. She'd been so disgusted she'd run home and stayed awake, waiting for him to come back just so she could give him a piece of her mind.

Three months! And this was what happened. Honestly, this is not what she expected marriage to be like.

"You followed me, you little spy!" Thomas spat back. His eyes flashed with anger as he advanced on her, his face contorted in rage. "I saw you sneaking in the window in the tavern. You little….How dare you spy on me?"

"Why shouldn't I?" Maria demanded back, instinctively backing away from him, placing a chair between her and her irate husband. He was drunk, she could tell by the stench of alcohol on his breath. But there was something more. Something that made her skin tingle slightly. There was something…off in his eyes. Yes, they were shining like a drunk lunatic, but there was something deeper. A strange pulsing anger that she'd never seen in him before. And though she didn't want to believe it, it scared her.

"I wanted to know why you would come home so late! Why you would sneak out in the middle of the night! I wanted to know why you were barely speaking to me lately! And now I know why!" Her face was flushed with anger, but it was nothing in comparison to the primal twist of Thomas's lips as he advanced on her once again. Maria stepped away from her chair-shield and tried to back up more, but he grabbed her wrist and shoved her up against the cold, clammy stone wall of their tiny home. He leered in her face.

"I do what I want, woman," he snarled at her. "And you can't keep me from seeing her."

"What's her name?" Maria demanded, trying not to cringe at the way he was crushing her wrist in his large, meaty hand, trying not to shudder at the pulsing fire behind his green irises. She had no idea what had brought on this sudden, horrifying change in his behavior, but it scared and infuriated her at the same time. And she wanted to know why.

"That's none of your business!" he yelled, then with a flick of his powerful arm, honed from years of pulling up nets of fish from the ocean's dark depths, he tossed her to the side as if she was nothing more than a ragdoll. Maria landed on the floor in a heap and struggled to climb back to her feet.

Thomas was stalking towards the door, and Maria's eyes narrowed with anger. No way she was letting him go out again, to be with his new girl.

"No!" she yelled and leaped to her feet. She ran forward and blocked the door, cutting off his access to the foggy darkness outside. She stood her ground, barring the wooden door. "I won't let you go back out there tonight."

"You can't tell me what to do!" he yelled at her. "Get out of my way!"

"Not on your life," Maria growled, her eyes narrowing, daring him to do something about it.

To her astonishment, he did.

Once more that huge, meaty fist clamped around her wrist, and though she fought to keep her ground he flung her to the side. Once more, Maria's slim body met the floor as she crashed down onto the hard, stone ground. She struggled to rise again and glared wickedly up at him.

"This isn't the man I married," she said as he began to pull open the heavy wooden door. Tendrils of mist crept into the house's interior, made to seem almost like sentient fingers as they were colored by the flickering fire in the hearth on the far side of the room.

Thomas paused for a moment and looked back at her. Their eyes met, and Maria stared up into the face of her husband who now suddenly seemed so foreign and unrecognizable, like she didn't even know who he was.

And for a moment, it almost seemed like this new, strange façade suddenly faded, and she could see the man she once knew underneath. His eyes gentled for a moment, the anger and primal ferocity left his weather-beaten face, and he looked down at his young wife with something almost akin to fear and confusion.

But then it was gone, and the anger came back tenfold. Her Thomas was gone.

"I don't care about the Thomas you married," he snarled at her. "Don't stand in my way, you sniveling brat."

With that, he turned and stomped out of the doorway into the darkness beyond. The door slammed shut behind him, and Maria could hear his heavy boots pounding the damp cobblestone streets outside. Only when she could not hear that sound anymore did she allow herself to burst into tears.

When Maria awoke the next morning, Thomas was not there. At some point in the night, she had managed to crawl onto her bedroll near the hearth. His remained empty, and when morning light, made grey and pallid by the mist that hung low over the tiny seaside town, filtered through the dirty windowpanes Maria found that his blankets were unused, and his presence was absent from the house.

Then there was a pounding on the door. Maria's heart leaped into her throat as she scrambled to her feet and hurried to find who had come to her home. She half feared, half hoped it would be Thomas, either home to apologize or to fight some more.

But, why would he be knocking?

Maria pulled open the heavy wooden door, disappointed to see that the outside world was still veiled in damp mist. But she was even more disappointed to see that her morning visitor was not Thomas, but a wife of another fisherman. Maria knew her only too well, as the wives of the fishermen tended to band together to support each other whilst their husbands were on long, dangerous trips, and being from such a small town, everyone knew everyone else.

Maria knew this woman who was so often a happy, smiling, cheerful young woman who was always ready to encourage. So Maria knew that there was something very wrong when she saw a look of pure fear and anxiety etched onto the woman's young features.

"Maria," she said, her voice tight. "You need to come down to the docks. Now."

And so she did.

And there was many a night after that she wished she had not. Down near the docks that jutted out into the sea and gave safe harbor to the many fishing boats that belonged to the men of the village, was a small crowd of onlookers. They were down on the beach, crowded around something which Maria could not see from this distance. She quickened her pace, anxious to find what had the crowd so intrigued.

She pressed past two fishermen and when it was understood who she was, she was let through easily.

When Maria finally was able to fight her way through the crowd and lay eyes on what had them so shocked, her eyes widened and her hands went to her mouth.

It was Thomas's fishing boat.

Its state was shocking. The small, two-man vessel was smashed in on one side, its mast broken and dragging the sail in the sand. Ocean water washed over the beaten and broken wooden boards that made up the hull. But what was most shocking was the long, claw-like marks along its sides, as if some creature had dug its talons into the wood.

"We found it this morning," a deep voice said behind her. Maria glanced with tear-filled eyes, toward one of the fishermen, one whom she had seen many times. His usually rough, stoic face was pale. "I never seen nothin' like it b'fore."

"Where's Thom?" were the only words that Maria could force out of her lips. "And Teague?"

Teague was Thomas's fishing partner. If Thomas had gone missing from this boat, than Teague would be gone, too, surely.

"Teague wasn't with 'im," the fisherman replied. "I saw 'im go out late last night. No one with 'im. Then this morning….this appeared."

"Where's Thomas?" Maria whimpered again, her voice catching in her throat. "Where's my husband?"

A heavy hand was rest upon her shoulder, but Maria didn't look to see who it was, because her eyes were closed tightly and tears were streaming down her cheeks.

"We don't know," another voice said. "Thom is gone."

A/N: I must apologize for a Arthur/Merlin-less chapter, but as the title of this chapter says it is a Prologue, and therefore is merely here to set the stage for the rest of the story. Merlin and Arthur will be appearing in the next chapter, so I hope you come back and read!