Beneath the rock and cockleshells, hidden below the center of the city, was the nautilus hall, shaped like a great horn curled in on itself and so large you could fit an armada of ships inside its curved walls. It had been enchanted long ago, a gift from a prince to his father before he took the throne himself, and it was the heart of sildroher power. Its base flowed with seawater and the level might be raised or lowered while the rest of the hall remained dry, so that the sea folk could practice their harmonies in both elements—water or air, as the spell required.
Song was not just a frivolity then, something meant to entertain or lure sailors to their doom. The sildroher used it to summon storms and protect their homes, to keep warships and fishing boats from their seas. They used it to make their shelters and tell their histories. They had no word for witch. Magic flowed through all of them, a song no mortal could hear, that only the water folk could reproduce. In some it seemed to rush in and out like the tide, leaving little in its wake. But in others, in girls like Ulla, the current caught on some dark thing in their hearts and eddied there, forming deep pools of power.
Maybe the trouble began with Ulla’s birth and the rumors that surrounded it. Or in her lonely childhood, when she was shunned for her sallow skin and strange eyes. Or maybe it began not with one girl but with two, on the first day Ulla sang with Signy, in the echoing cavern of the concert hall.
They were still just girls, neither yet thirteen, and though they had been educated in the same places, attended the same tidal celebrations and hunts for sturgeon, they were not friends. Ulla knew Signy because of her hair—vibrant red that flashed like a warning and gave her away wherever she went. And of course Signy knew Ulla with her black hair and her gray-tinged skin. Ulla, who had sung a song to scrape barnacles from her nursery when she was just an infant; who, without a single lesson, had hummed a tune to set the reedy skirts of her kelp dolls dancing. Ulla, who wielded more power in a single simple melody than singers twice her age.
But Ulla’s classmates did not care about the surety of her pitch, or the novelty of the songs she composed. These things only made them jealous and caused them to whisper more about her murky parentage, the possibility that her father was not her father at all, that her mother had returned from a summer ashore with some human boy’s child in her belly. It was not supposed to be possible. Humans were lesser beings and could not breed with the sildroher. And yet, the children heard their parents whisper and gossip and so they did the same. They claimed Ulla had been born with legs, that her mother had used blood magic to fashion her a tail, and taken a knife to the skin of Ulla’s throat to give her daughter gills.
Ulla told herself it wasn’t true, that it could not be, that her father’s lineage was clear in the pattern of her silver scales. But she could not deny that she looked like neither of her parents, or that occasionally, when her mother braided Ulla’s hair and set pearl combs above her ears, there was an expression on her face that might have been fear, or worse, disgust.
Ulla sometimes dreamed of a life in distant waters, of finding other sea folk somewhere who would want her, who would not care what she looked like or who had sired her. But mostly she dreamed of becoming a court singer—venerated, valued. She imagined herself arrayed in gems and cusk bones, a general with a choir as her army, commanding storms and building new cities for the king and queen. Court singers were appointed by the king and nearly always carried noble blood. But that did not stop Ulla from hoping or from clinging to that dream when she was left alone in the nautilus hall as the other students drew into pairings for duets or formed groups for ensembles, when yet again she was forced to sing with the choirmaster, his face soft with pity.
All of that changed the first time she sang with Signy.
On that day, the concert hall had been nearly emptied, the rocks at its base exposed to the dry air as the sea outside flowed on. The students lay upon the smooth stones, faces bored, a sinuous pile of curled tails and pretty cheeks resting on damp forearms. Signy was at the periphery of the group, leaning into their slippery bulk. All morning she had cast Ulla sour glances, her pink conch mouth turned down at the corners, and it was only when the choirmaster began pairing them off for duets that Ulla understood why: Lis, Signy’s usual partner, had not come to class. Their numbers were even and Signy would be forced to sing with Ulla.
That day the class was practicing simple storm magic with little success. Each pair made their attempt, and some managed to summon a few puffs of cloud or a mist that might generously be called a sprinkle. At one point, a rumble of thunder began, but it was only the growling of young Kettil’s stomach.
When at last it was time for Ulla and Signy to perform, they slid onto the spit of rock that served as a stage, Signy keeping her distance as her classmates tittered at her misfortune.
Ulla thought for a moment of an easy melody, something that would end this humiliation quickly. Then she shoved the thought away. She hated Signy for being so afraid to be paired with her even briefly, hated her classmates for their stifled giggles and sly eyes, but mostly Ulla wished that she could kill the thing inside herself that still longed for their approval. She cast Signy a cold glance and said, “Follow me. If you can.”
Ulla began a spell she’d been practicing on her own, a staccato tune, full of sudden syncopation. She leapt nimbly from note to note, plucking the melody from the secret song she could hear so clearly, happy to leave Signy behind to struggle with her sweet, wobbly voice.
And yet wherever Ulla led the song, the other girl followed with grim determination.
Gray-bellied clouds formed high above them in the ceiling.
Ulla glanced at Signy, and the first rain began to fall.
There are different kinds of magic. Some call for rare herbs or complicated incantations. Some demand blood. Other magic is more mysterious still, the kind that fits one voice to another, one being to another, when moments before they were as good as strangers.
The song rose louder. Thunder rolled and shook the nautilus hall. The wind howled and tore at the hair of the students on the rocks.
“No lightning!” cried the choirmaster over the din, waving his arms and thumping his massive orange tail.
The song slowed. The other students mewled and thrashed. But Ulla and Signy didn’t care. When the last note had faded, instead of turning to their classmates, hoping for praise, they turned to each other. The song had built a shield around them, the shelter of something shared that belonged to no one else.
The next day Lis returned to class and Ulla steeled herself, prepared to be stuck with the choirmaster once more. But when he told them to pair up for duets, Signy pressed her hand into Ulla’s.