I was foaled at twilight, he said gravely. Or perhaps I was hatched; I cannot remember. It was long ago. Sometimes I run, and sometimes I remember to fly. And thus am I named.

Vasya stared. “But you are not a bird.”

You do not know what you are; can you know what I am? retorted the horse. I am called Nightingale, and does it matter why?

Vasya had no answer. Solovey had finished her porridge and put his head up to look at her. He was the loveliest horse she had ever seen. Mysh, Buran, Ogon, they were all like sparrows to his falcon. “Last night,” Vasya said hesitantly, “last night, you said you would let me ride.”

The stallion neighed. His hooves clattered on the floor. My dam said I should be patient, he said. But I am not, usually. Come and ride. I have never been ridden before.

Vasya was suddenly dubious, but she replaited her tangled hair and put on her jacket and cloak, mittens and boots, which she found lying near the fire. She followed the horse into the blinding day. The snow lay thick underfoot. Vasya eyed the stallion’s tall bare back. She tried her limbs, and found them weak as water. The horse stood proudly and expectantly, a horse out of a fairy tale.

“I think,” said Vasya, “that I am going to need a stump.”

The pricked ears flattened. A stump?

“A stump,” said Vasya firmly. She made her way to a convenient one, where a tree had cracked and fallen away. The horse poked along behind. He seemed to be reconsidering his choice of rider. But he stood alongside the stump, looking pained, and from there Vasya vaulted gently to his back.

All of his muscles went rigid, and he threw his head up. Vasya, who had ridden young horses before, was expecting something of the sort, and she sat still.

At last the great stallion blew out a breath. Very well, he said. At least you are small. But when he walked off, it was with a mincing, sideways gait. Every few seconds he turned his head to see the girl on his back.

THEY RODE ALL THAT DAY.

“No,” Vasya said for the tenth time. Her night in the snowy forest had left her weaker than she had realized, and it was making a hard task harder. “You must put your head down and use your back. Right now, riding you is like riding a log. A large, slippery log.”

The stallion put his head round to glare. I know how to walk.

“But not how to carry a person,” Vasya retorted. “It is different.”

You feel strange, the horse complained.

“I can only imagine,” said Vasya. “You need not carry me if you do not wish to.”

The horse said nothing, shaking his black mane. Then—I will carry you. My dam says it grows easier in time. He sounded skeptical. Well, enough of this. Let us see what we can do. And he bolted. Vasya, taken by surprise, threw her weight forward and wrapped her legs around his belly. The stallion careened between the trees. Vasya found herself whooping aloud. He was graceful as a hunting-cat and made about as much noise. At speed, they were one. The horse ran like water and all the white world was theirs.

“We must go back,” said Vasya at length, flushed and panting and laughing. Solovey slowed to a trot, his head up, his nostrils showing red. He bucked with sheer high spirits, and Vasya, clinging, hoped he would not have her off. “I am tired.”

The horse pointed an ear at her in a dissatisfied way. He was hardly winded. But he heaved a sigh and turned. In a surprisingly short time, the fir-grove lay before them. Vasya slid to the ground. Her feet struck the earth with a great jolt of pain, and she sank, gasping, to the snow. Her healed toes were numb, and some hours’ ride had not improved her weakness. “But where is the house?” she said, gritting her teeth and heaving herself to her feet. All she saw was fir-trees. Day’s end mantled the wood in starry violet.

It cannot be found by searching, said Solovey. You must look away just a little. Vasya did, and there, in a quick flash at the edge of her vision, was the hut among the trees. The horse walked beside her, and she was a little ashamed that she needed the support of his warm shoulder. He nudged her through the door.

Morozko had not come back. But there was food on the blazing hearth, laid by invisible hands, and something hot and spicy to drink. She dried Solovey with cloths, brushed his bay coat, and combed the long mane. He had never been groomed before, either.

Foolishness, said the horse, when she began. You are tired. It makes not the slightest difference whether I am brushed or not. But he looked vastly pleased with himself regardless, when she took extra care over his tail. He nuzzled her cheek when she had done, and he spent the whole meal inspecting her hair and face and dinner, as if suspecting she’d kept something back.

“Where do you come from?” Vasya asked, when she could hold no more and was feeding the insatiable horse bits of bread. “Where were you foaled?” Solovey did not reply. He stretched his neck out and crunched an apple in his yellow teeth. “Who is your sire?” Vasya persisted. Still Solovey said nothing. He stole the remainder of her bread and ambled away, chewing. Vasya sighed and gave up.

VASYA AND SOLOVEY WENT out riding together every day for three days. Each day, the horse bore her more easily, and, slowly, Vasya’s strength returned.

When they returned to the house on the third night, Morozko and the white mare were waiting for them. Vasya limped across the threshold, pleased that she could manage it on her own two feet, and stopped short, seeing them.

The mare stood by the fire, licking idly at a chunk of salt. Morozko sat on the other side of the blaze. Vasya slipped off her cloak and approached the oven. Solovey went to his accustomed place and stood expectantly. For a horse that had never been groomed, he adapted very fast.

“Good evening, Vasilisa Petrovna,” said Morozko.

“Good evening,” said Vasya. To her surprise, the frost-demon was holding a knife, whittling a block of fine-grained wood. Something like a wooden flower was taking shape under his deft fingers. He laid his knife aside, and the blue eyes touched her here and there. She wondered what he saw.

“Have my servants been kind to you?” said Morozko.

“Yes,” said Vasya. “Very. I thank you for your hospitality.”

“You are welcome.”

He was silent while she groomed Solovey, though she felt him watching. She rubbed the horse down and combed the snarls from his mane. When she had washed her face and the table was laid, she tore into the food like a young wolf. The table groaned with good things: strange fruits and spiky nuts, cheese and bread and curds. When at last Vasya sat up and slowed down, she caught Morozko’s sardonic look. “I was hungry,” she said apologetically. “We do not eat so well at home.”

“I can well believe it,” came the reply. “You looked like a wraith at midwinter.”

“Did I?” said Vasya, disgruntled.

“More or less.”

Vasya was silent. The fire fell in on its core and the light in the room went from gold to red. “Where do you go when you are not here?” she asked.

“Where I like,” he said. “It is winter in the world of men.”

“Do you sleep?”

He shook his head. “Not as you would think of it, no.”

Vasya glanced involuntarily at the great bed, with its black frame and blankets heaped like a snowdrift. She bit back the question, but Morozko caught her thought. He raised a delicate eyebrow.