A monster storm was brewing that night, the kind men bragged about surviving for years afterward. The kind of storm that arrived so suddenly and struck so mercilessly that nothing earthly could be said to have caused it, only a curse from the fates. Madeline knew the sailors thought she had brought it down on them. She saw the way they stared at her, as if they would like nothing better than to throw her over the side. She heard the things they muttered as she passed. Quietly at first, and then louder and more frequently as the sky grew dark and the winds began to howl:

"Bad luck to have a woman aboard."

"She'll send us to the bottom of the sea."

Madeline pulled her shawl tighter around herself and averted her eyes from them. Drops of rain and seawater stung her face and dripped down her neck, soaking her tattered clothes. She wondered if she should go below again, but it was no drier there than up here. Matthew had said he would be on deck. As the ship's first mate, it was his duty to keep the men together in a crisis.

Finally, she caught sight of him on the forecastle, looking preoccupied. Matthew was a big man, a strong man, with a dramatic black beard and a naturally commanding voice. When he gave orders, people obeyed him. Just the sight of him made some of Madeline's anxieties recede. The fingers of her right hand instinctively clasped the locket he had given her, the one he himself had put around her neck. Clutching her soggy skirts with her other hand, she ran up the forecastle steps, calling his name.

"Matthew! Matthew, wait for me!"

He didn't turn around until she caught his wrist. The momentary anger in his eyes took her by surprise. "You shouldn't be up here," he said roughly.

"I was scared," she said in a small voice. "I wanted to find you."

His expression softened slightly. "I told you this life would be hard, but you begged me to take you with me when we set sail. If you hadn't assured me that you could handle it, I would have left you back in Liverpool." His arm slipped around her waist, but she pulled away.

She pouted. "I think you love this ship more than you love me."

"At least the ship doesn't moan and complain every time there's a little drizzle." Matthew turned his back to her and began shouting orders again.

"Matthew! How could you –"

Without even turning around, he reached back and slapped her across the face. "I have work to do," he said flatly. "Now get below."

Never in her life had Madeline felt so ignored. She felt tears mingling with the water already on her face. Turning on her heel, she rushed down the stairs and over to the starboard railing. The other sailors, having witnessed the entire scene, jeered at her as she hurried by. Now that they could be sure Matthew's attention was on other things, they felt free to say whatever they wished.

"Cry as much as you want, missy, it won't save you from the sharks."

"Do you sink or float? I hear witches sink like a stone."

Keeping her gaze on the tumbling black waves, doing her best to ignore everything on the ship, Madeline never heard the lookout cry "Reef!" There was a sudden, jarring impact; her hand slipped on the wet railing. Even had anyone nearby been inclined to help her, she would have gone over far too fast for anyone to catch her. Her last thought before she hit the icy ocean was regret that Matthew would surely think she had thrown herself overboard.

The merman found her, unconscious, some hours later. It had been the skirts that saved her; layers of sodden fabric caught on the rocks of the reef. The merman crept silently up over the rocks to inspect his find. It was rare that they found one alive, these days. A female was even more uncommon. His long, dolphin-like tail swished back and forth in the water as he pondered what to do with her. Some of the water splashed gently on her face. Her eyes fluttered, then opened wide.

The merman pulled back a few inches, then flashed her his most charming smile. He hated it when they screamed. To his delight, the girl did not seem very surprised to see him. Perhaps she had heard tales of his people in her own lands.

"Are – are you a merman?" she asked hesitantly, though his silver-smooth tail and neck lined with greenish gills made the answer obvious. Rather than answer in words, the merman merely nodded, then opened his mouth and released a sentence of rhythmic clicks – the only sounds he could make above water. That noise would be enough to call his fellows to him. Before the girl could ask any more questions, he took her wrist and pulled her beneath the surface.

Madeline had been sure she was dreaming when she had opened her eyes to find the merman's face hovering above her own. His features held an unnatural beauty; even his smile was perfect, although the sharpness of his even teeth gave her a twinge of unease. When he dragged her under, she felt sure he meant to drown her, like mermaids were said to do in some of the sailor's tales. Instead, she found herself able to breathe normally, as if it were air instead of water she was swimming in.

The merman introduced himself as Tharon, and apologized for startling her. His voice sounded alien and distant to her ears, although he was perfectly understandable. They waited in silence ten feet below the surface until lithe shadows in the distance announced the approach of three other mermen. Tharon whispered the names of all three into her ear. When they drew closer, the four of them spoke a few words in their own language that Madeline could understand no more than she could French.

Apparently they decided to take her somewhere, though, because in mere moments she felt Tharon tugging on her wrist as he swam forward effortlessly. The other three flanked them like an honor guard. After a few minutes, Tharon grew tired of dragging her along and let go of her arm. Instantly, the air was expelled from her lungs in a cloud of bubbles. Water poured in through her nose, choking her. Madeline began to panic, and thrash about. Just as she thought she would surely drown, a strong hand gripped her other wrist and her air returned. The bubbles cleared. She was looking into the smirking face of another merman, the one called Chiden. Tharon was above them, having taken Chiden's place in the formation.

The mermen continued their sadistic game all the way back to their caves, making each interval she went without air longer. They ignored Madeline's breathless, furious protests, smiling knowingly amongst themselves. The last time, black specks flew across Madeline's vision as she nearly blacked out. Although it seemed an eternity to her, less than an hour passed before they reached their destination.

She saw other mermen, and mermaids: achingly beautiful women with flowing golden hair, innocent blue eyes, and red lips that always seemed poised to blow a kiss. She heard their glittering laughter as her escort dragged her by, and realized what she must look like to them: bedraggled, half-drowned, floating along in layers of ridiculous garments that tangled her legs and arms at every stroke. Like something the cat dragged in, completely out of her element. Madeline had always considered herself a fair swimmer, but the graceful movements of these alien creatures put her to shame.

The largest cave was also the deepest, heated by a deep fissure in the sea floor. It was surrounded by tropical fish and lavish corals in all the colors of the rainbow, more like the Caribbean than like Europe. Mats of waving seaweed tugged at her bare ankles, prompting Tharon and an unknown mermaid, giggling, to pull up masses of the stuff and drape it all along Madeline's head, neck, and arms.

Inside the cave, she was brought before a panel of white-haired, dignified merpeople, each seated on large chunks of black stone. Madeline realized that these must be their kings and queens, or something like it. All of them were just as hauntingly beautiful or handsome as the merpeople outside, none showing any signs of age other than their hair, or perhaps a few more subtle creases around the eyes. She wondered briefly if they went on looking young until the day they died. Did merpeople ever die? None of the tales she'd heard had offered any clues.

A sharp-faced woman with short hair near the center of the group asked Madeline her name, where she had come from, and how she came to be on their reef. Her tail was that of a barracuda, with gray and black scales.

"Madeline Curry, if it pleases your grace," she said, trying awkwardly once to curtsy in ballooning skirts before giving it up as a bad job. Madeline had never had much experience dealing with the nobility in her life, even the human kind. Some of the ruling council hid smiles at her floundering. Others continued to stare at her with a disturbing, almost hungry look. "I was on board the H.M.S. Thrush, a navy vessel from England, but we were caught in a storm and I was knocked over the side."

The woman raised a hand to interrupt her. "We know the kind of ships you speak of, but we were not aware that they allowed women to be sailors."

"I was with my husband, Matthew Lyons. He captains the Thrush." Technically Matthew, who was only the first mate, had not yet asked her to marry him, but she felt the need to impress the merpeople. Maybe it was the way they looked at her, weighing her up, as if she was a slab of meat at a butcher's shop.

"We saw that ship go by safely two days ago," said the barracuda woman. "The storm made approaching it too dangerous. It is bad luck for you. If it had been closer, perhaps we could have returned you to your own people."

"It's coming back," Madeline said quickly. The thought of staying down here forever in her current state, or worse, being left to drown, was too horrible to contemplate. "Matthew said that if the winds cooperated, we would be returning home in a week."

"A week," said the woman thoughtfully. Her mouth curled greedily as she said a few sentences in their language to the others around her, getting several nods of agreement in return. "How many sailors? They will be returning down the same route they came?"

"A few hundred, if all survived the storm," she said uncertainly, not understanding why they wanted to know. "And yes, I'm sure of it."

"Excellent," the woman murmured. "If this is true, you have done us a great favor. The others have agreed to spare your life in return for this favor, and grant you a wish besides."

Madeline's heart jumped in her chest. She knew exactly what she wanted. She had wanted it ever since she caught her first glimpse of a mermaid, swimming around aimlessly outside the caves. "There is a way to make me… one of you," she said slowly, not wanting to say it straight out.

The woman's lips twitched, as if she had known all along what Madeline would ask. "Yes. Is this your desire?"

Sailors' stories varied sometimes on the details, but what they all agreed on was the exceptional, enticing beauty of mermaids. She had seen it for herself, now. If she looked like that, Matthew would never look at anyone else. He would stop leaving on voyages for years and years at a time. He would stay with her. Madeline drew up her head and looked the barracuda woman firmly in the eye. "Yes."

"Very well," she said with a faint, unpleasant smile. "When you next meet your Matthew, it will be as a – what is the word you use? Mermaids. Yes. A mermaid. A daughter of the sea."

Madeline held her breath as Tharon and Chiden took her hands and led her out of the cave, down into the crack in the ocean floor, where the water felt hot enough to boil. Deeper and deeper they went, and when they finally released her, the water rushed in, scorching her from the inside out. Her legs began to tingle, then to burn, and finally to melt completely away, leaving her helpless and alone in the terrible darkness.

A week later, Madeline lounged on the rocks, waiting for Matthew's ship to be sighted over the horizon. She wore nothing from the waist up except for his locket, and below that her parrotfish tail, all red and gold scales, dangled lazily in the water. When the Thrush's familiar silhouette appeared in the distance, she sat up straighter and began brushing her hair with a carved bone comb. The ship drew alongside her. She pretended not to notice the men staring at her from the deck, not until the one she wanted to see arrived. The men tending the sails ceased their work; the sails grew limp, and the ship slowed, began to drift sideways. Madeline uncurled herself from the rock and dove easily into the water, staying next to it.

There, at last, was Matthew, his lips forming the sounds of her name, his face disbelieving. She beckoned to him, and he leaned over the railing immediately. How could he resist her, like this? None of them could. One by one, the sailors began diving overboard, their faces masks of delight, all of them trying desperately to reach her. One by one, they disappeared below the surface before they could even get close. She saw the other mermaids swimming around her, their features subtly altered to become more angular, more predatory. The flesh melted away from their faces, leaving an almost skeletal visage, framed by two rows of very sharp teeth. In the water, they were faster than even the most desperate human could hope to be. Blood quickly dyed the water a dark red.

Madeline looked around her in horror. She had never meant for any of this to happen. Her allure was unconscious and irresistible. Matthew resisted the longest, his arms straining to hold on to the railing while the rest of his body fought to dive off it. Eventually, however, he grew weary and let go, tumbling over the side. In one stroke she was upon him. She took his wrist and tenderly touched his face, looking into his eyes. There, mixed in with the mindless desire she'd seen on the faces of all the other sailors, was true horror. She wondered what he saw when he looked at her. Whether she resembled her fellow daughters of the sea, who even now were returning en masse to their caves, sated from their bloody feast.

When she looked at him, all she felt was hunger, equally irresistible.

Three days later, when the H.M.S. Thrush did not return to port on its scheduled date, another ship was sent to determine what had become of it. In the spot where it had last been spotted, they found only a few scraps of cloth and a golden locket, tied neatly around a floating spar and marked with the initials MCL. After nearly a week of searching, they found the heavily damaged ship drifting far off course without a soul on board.

The official story was that disease, contracted during the voyage, had killed the crew down to the last man and that storms had washed the bodies away. But sailors are notorious for their loose lips, and tales of the Thrush's fate were told for years afterward. The spot it had passed through on its way back home grew a reputation; many men refused to sail there, and would go miles out of their way to avoid passing through. When asked why by their skeptical superiors, they grew reluctant to speak of it, and would say only that they had heard that a terrible monster dwelt in those waters, and that she would never, ever be satisfied.