The deep black night sky over the remote stretch of the Scottish highlands was decorated with thousands of pinpoint stars strewn thickly over the vault of the heavens, some faint and some bright, on this unseasonably clear night in spring. Jack stood at the door of his little cottage, a jacket held tightly over his nightshirt against the chilly night air, and looked across at the large stone barn not far away, from which he heard restless stamping of hooves and insistent vocalizations, like horses whinnying, but not exactly.

The thestrals were awake and moving about uncharacteristically; at this hour they all ought to have been sleeping. Something was disturbing them, but Jack didn’t know what it was. He would have to check on them. Jack shoved his bare feet into boots that stood just outside the door and began to walk through the grassy field toward the barn, trying to imagine what it was that had aroused the beasts. Had some kind of varmint crept into the barn? A snake, perhaps? A fire? No, no way the barn could be on fire. A prowler? Muggles could not see either the cottage or the barn, and a rogue wizard or witch would have been repelled by the wards that had been placed around this estate.

People said that animals could sense impending disaster. There were anecdotes about pets and farm animals that were seen to act strangely just before an earthquake struck, but Scotland was not prone to earthquakes. Jack trudged across the wet grass, wondering.

By the time he had reached the barn door, Jack had run out of possible explanations for his animals’ unrest. From his jacket pocket he pulled the wand that he always kept with him. �Lumos maxima� he said, and the broad stone façade of the barn, with its tall, wide wooden doors, leaped into view in the sudden bright light. Jack unlatched the doors and pulled one door open far enough to allow him to slip into the barn.

The barn was much bigger on the inside than it appeared on the outside. Rows of tall wooden stalls provided space for more than one hundred thestrals, great beasts with long legs and leathery wings that they always kept folded compactly at their sides when they were sleeping. But now many of them were on their feet, moving restlessly in the aisles between the rows of stalls, nodding their great heads and pawing their hooves in the straw that covered the barn floor. Some had half-unfolded their wings, although there really wasn’t enough room in the barn for that, and they brushed against one another and against the posts at the ends of the stalls.

During his childhood in a nearby village, Jack had been witness to the death of a neighbor boy who had been thrown from his horse and had broken his neck. Ever since that day, Jack had been able to see thestrals, the “black horses of death�, and this ability had allowed him to be employed as a thestral keeper. He knew these animals individually, which ones were the aggressive leaders of the herd, which ones were the followers.

Jack’s eyes scanned rapidly over the floor, looking for a snake or other varmint, but he knew that such a creature, if it were here, would have retreated into a dark corner as soon as he had appeared with his light. He began to walk along the row of stalls, weaving between the thestrals moving about in the aisles, and flicked the light into each stall, searching for an intruder.

He had almost reached the far end of the barn, finding nothing, when suddenly a commotion erupted behind him. He whipped his head around to see all the still recumbent thestrals scrambling to their feet while the already standing beasts headed rapidly toward the door. which was still slightly ajar, and pushed it open. They galloped out into the field, followed closely by the rest of the thestrals, spread their wide black wings, and leapt into the dark sky.

Jack ran after them, but by the time he reached the barn door, now wide open, he knew that there was no chance of calling them back. He stood in the open doorway, his wand hanging limply in his hand, straining his eyes to spot the large but rapidly disappearing herd. But they were black against the black sky, and nothing could be seen except a small patch of sky that appeared momentarily bereft of stars.

Jack could only hope that his herd, which he had been charged to tend and protect, knew what they were doing and where they were going, and that they would eventually come back of their own free will. He turned and faced the interior of the barn again. �Accio varmint!�, but nothing appeared. Whatever had stirred up the thestrals had not been a snake.

The great beasts flew strongly toward the southwest, along a path in the sky that they had followed numberless times before, but this time they were following an overwhelming scent of blood, which their keen senses could detect, although Jack had smelled nothing. Despite their appearance of other-worldly horses, they did not graze on grass or have the round bellies of pasture-feeders. They fed on meat � Jack fed them on fish and on the leftovers of sheep slaughtered by wizard crofters. They also picked up the occasional road kill, earning themselves the nickname “the vultures of the highlands� by those who could see them. Like reptiles, they had low metabolic rates when at rest, but when they flew, they burned more food, like mammals. Like albatrosses, their wide wingspan enabled them to soar while flapping their wings only infrequently, and like sharks, they detected the faintest whiff of blood.

Onward they went, a vast black flock with wings outstretched, occasionally giving a flap that provided great forward thrust, so that they glided with great speed, unseen by Muggles and even by witches and wizards who had never witnessed death. The oldest, most experienced thestrals were in the lead, guided by the smell of blood, which grew stronger and stronger. That scent was leading them straight towards Hogwarts School of Witchcraft and Wizardry, an old destination, but for a new reason. All the old, familiar landmarks unspooled before them &ndash: roads, rivers, lakes, villages, hills, crags – all the checkpoints by which they steered themselves four times a year, when they were guided by vision rather than scent. But this time the thestrals were not going there to be hitched to carriages on the outskirts of Hogsmeade. Something else was happening which had nothing to do with drawing carriages.

Perhaps, they thought, it would be an opportunity for feasting, a mass slaughter of livestock, or some sort of natural disaster, such as a flock of sheep killed by a landslide. Or perhaps a pair of trucks carrying sheep had gone off the road and had tumbled down a steep hillside, coming to rest at the bottom, wheels still spinning and bodies of sheep strewn all around on the ground. Would there be enough for all the thestrals?

The darkness was not a problem; their large, white eyes, seemingly without iris or pupil, could see in the darkness like the eyes of owls or cats. But the sky was lightening, from black to a deep, dark velvet blue, and the faintest stars were winking out. Somewhere, far beyond the eastern horizon, the new day was approaching. With their bony noses thrust forward and their black manes and tails streaming behind in the wind of their flight, the thestrals approached Hogwarts as the sky paled to the point that only the brightest stars remained, losing their brightness fast, and a broad ribbon of red stretched along the eastern horizon.

The thestrals were confused. The smell of blood was overwhelmingly strong, but nothing in the village was afoot, other than a few old men and women who had been standing out in the plaza but were now returning inside their buildings. But the sign of hundreds of human footprints on the dirt road, completely obliterating the usual cart tracks in the dirt, and all pointing in the same direction – towards Hogwarts – told the flying creatures all they needed to know. They wheeled in the sky, adjusting their line of travel a little, and made straight for Hogwarts. The reason that they had been called out in the middle of the night awaited them there.

The pink glow of impending sunrise cast its hues over the castle’s towers as the thestrals overtopped the wall around the castle grounds, over which some citizens from Hogsmeade were still clambering, filling the air with the clamor of shouts and war-cries. The thestrals sailed over the walls at a high altitude. They did not yet know what was going on, but the smell of blood was overwhelming. That was not just roadkill or an overturned sheep transport. Something profoundly evil was going on, they knew, and it was their fate to be there. They had a role to play. Hogwarts needed them for more than just pulling carriages.

A melee of fighting was going on in the grounds around the castle, a swirling, surging mass of human beings and other creatures in all-out war. On the ground, the thestrals could see those other horses, the ones that could not fly but which could wield bows and arrows. Two giants were stamping through the field of battle, crushing combatants with their gigantic feet. With a swing of their massive arms, the giants knocked men and women sideways left and right. The centaurs’ arrows were aimed mainly at human combatants, who were firing hexes and curses in all directions in a mad swirl of arms, legs, robes, bangs, and flashes, but some of the arrows struck the giants, who seemed scarcely to notice their stings as they continued their murderous rampage.

�An enemy of the centaurs is my enemy� thought the oldest and most experienced thestral, the one who had led the entire group in their desperate pre-dawn journey through the dark skies, following the scent. He saw the job that only a thestral could do, with its massive wings and cruel, knife-like fangs. He gave a whinny that was like the noises Jack had heard in the barn a few hours previously, only many times louder, so that all the other thestrals could hear, and he plummeted toward the tallest giant, jaws agape, fangs bared, and bit off a great mouthful of flesh from the giant’s head as he struck the giant with a glancing blow.

The giant jerked his head around and gave a tremendous roar of rage and pain, but the other thestrals had seen what had happened, and they mobbed both giants’ heads, ripping with their jaws and striking with their razor-sharp hooves so that the blood poured down the giants’ faces and into their eyes. The giants struck out blindly with their club-like arms, and a few thestrals were batted away, but they recovered themselves in the air before they could tumble to the ground, and rejoined the fight, keeping up the relentless assault. The ground around the giants was fast becoming splashed with blood.

A smaller creature, which resembled the giants but was much shorter, was battering the giants’ legs and torsos with its fists, although the tree-solid giants seemed not to notice the blows. The thestrals ignored the smaller creature, which appeared to be on their side but which was not having much of an effect anyway.

The giants, lacerated and bloody, half blind, still roaring in pain, began to back up, seeking to get away from their tormentors. They backed away from the castle for several steps, then turned and lumbered away from the scene of the battle, stumbling over the bodies of the dead which they could not see, falling into craters in the ground where spells had blasted the earth away. The thestrals continued harrying them, flapping their great wings and striking the giants’ broad backs with knife-like hooves whenever the giants appeared to be slowing in their retreat from the field of war.

Finally the two giants reached the boundary wall, which they perceived by running into it. They stopped and felt the wall with their hands, leaving bloody smears on the stones, and then stepped over it with their huge legs and continued lumbering down the hill.

Some of the thestrals bent their heads to lick the blood off the stones, their sinuous black tongues making short work of the stains; in less than a minute, no trace of blood remained.

Folding their wings against their bodies, the thestrals walked back toward the castle on their skeletal black legs, looking like grim stilt walkers in the red light of the rising sun. No living persons were outside the castle anymore; they had all gone inside the castle to continue the fight. Even the centaurs were no longer to be seen. Unmoving bodies were scattered over the grass among the craters and scorched marks. Some had died without a mark on them; others had burns and blackened areas on their faces and clothes, but they were not bleeding and did not attract the thestrals’ attention.

But the great creatures themselves were spattered with the giants’ blood. The smell of it, so close to their nostrils, blood clotting in their manes, irritated them and made them uneasy. They turned their heads back over their shoulders, licking their own flanks, then began licking each others’ shoulders, faces, and manes.

Suddenly a noise like a massive explosion, coming from inside the castle itself, shook the air, echoing off the sides of the surrounding hills and spooking the thestrals, who cantered away from the castle toward the boundary walls. Shortly thereafter, jubilant people began streaming out of the castle in great numbers, laughing and crying and exclaiming all at the same time, and the great black horses spread their wings and began taking off into the air, at first a few of them, and then the oldest thestral, the one that the others followed as their leader. En masse the remaining thestrals took off, and they rose higher and higher until they were just black dots against the morning sky, visible to anyone on the castle grounds below because all the people had now witnessed death, but no one was paying any attention to the thestrals.

Back toward their barn and their fields they glided, with occasional flaps of their wide, leathery wings, but not with the speed and urgency of their pre-dawn flight only a few hours ago. The affairs of wizards, in their widest scope, were beyond the ken of the thestrals; they recognized and understood only their own small part in this day’s events, but they flew toward home with a sense of satisfaction and completion. What they had had to do, for whatever reason, they had done.

At the thestral farm, Jack was concerned. He had waited, and the thestrals had not returned. He did not go back to bed, but stood scanning the skies for a while until he realized that it was futile to do so, since he would not have been able to see the black thestrals returning again against a backdrop of black night until they were practically on the ground again. He went back into his cottage, lit the lantern, made himself a large mug of strong tea with plenty of sugar in it, and sat down at his table, the mug between his hands on the dark wooden tabletop, worn smooth and shiny by centuries of use.

He was not sure what to do The vision of the thestrals’ sudden elopement played itself over and over in his mind, as he searched his memory endlessly for overlooked clues that might prove to be the key to explain this unprecedented (in his experience) occurrence. Every fifteen minutes or so, he got up from his chair and walked out the door onto the path, more from a sense of urgency to do something than any real hope of seeing the thestrals standing between his cottage and the barn, for he felt sure that if they returned, he would hear them, and he heard nothing.

The sky began to lighten, and Jack, seated at his table, gave a deep sigh. The remains of his tea now sat in the bottom of his mug, a scant inch of cold, brown liquid, unappetizing because the sugar, which tended to settle to the bottom, made it unpalatably sweet. He knew what he had to do � send an owl to his supervisor describing what had happened, but not explaining it because he had no explanation. He wondered if he would be blamed for not latching the barn door behind him when he had first entered the barn at three a.m. His only defense could be that nothing like this had ever happened before.

He stood up and brought quill, ink and parchment to the table and laid these items out on the old wood surface in a neat row. If the thestrals had not returned by sunrise, he decided, he would write the letter.

As dawn approached and the sky became a brilliant pink, Jack stepped outside and checked the sky one more time. The thestrals had headed toward the southeast when they had left, he recalled, but he could not assume that they would necessarily return from the same direction, so he scanned all around the horizon. He would have been thankful to see them returning from any direction, but the sky was perfectly blank.

Jack re-entered his cottage and began to prepare breakfast. Normally he did not eat so early in the morning � it was only about four-thirty o’clock &mdash: but he was nervous and edgy, and in the back of his mind he knew that he was procrastinating about writing the message to his supervisor. So he took his time in sautéing the little sausages and then cooking his eggs, using low heat. Maybe some oatmeal too; that would be good, and the necessary stirring and simmering would use up some more time.

The sun rose, and the sunlight poured in through the windows of his cottage. Jack extinguished the lantern, placed his food on the table, and began to eat at a leisurely pace. The sight of the quill, ink pot , and parchment on the table nagged at him, and when he had finally finished eating and had cleared the table of dirty dishes, he stepped outside one last time, in a vain hope that he could see the thestrals returning.

Where in the world did they go? he asked himself. And for Merlin’s sake, why?

Just to make sure that he had accounted for every possibility, he walked over the dew-moist grass to the barn, unlatched the door, and looked inside to assure himself that the animals had not returned and somehow let themselves back into the barn, perhaps undoing the latch with their teeth in a manner never before seen. But that chances of that occurring were just about zero, he knew, and as he expected, the barn was empty.

Jack walked back to his cottage. This was a time of day, early morning, when he normally felt energized and uplifted, but today the blue sky, endless green grass dotted with rough gray boulders decorated with orange and yellow lichens, and the fresh smell of the breeze could not buoy his spirits. In the cottage he finally changed out of his nightshirt-and-jacket outfit into regular clothes and sat down to face the task of reporting that he had somehow lost all his charges.

The letter was not so difficult to compose as he had feared. He cleared his mind of anxious worries and wrote a straightforward, factual report of what had happened and what he had done, as an unbiased newspaper reporter might have written, with no intimation of blame or dereliction of duty, and no speculation as to what was going to happen next. Let his superiors fling blame about, if they would � he would not.

He rolled the parchment into a tight scroll, tied it securely, and fastened it to the leg of the brown owl that shared his cottage. With the owl perched on his wrist, he went out into the morning sun, where the owl spread its wings and flew off into the sky. He watched it go. It was easy to see against the blue.

About an hour later, Jack was working outside. He felt that he had done all he could about the thestrals. He had laid out some fish and sheep entrails in long wooden feeding troughs. Perhaps, if the thestrals were close enough to smell the meat and if they were hungry, it might lure them back. There was no breeze that morning, and hopefully the scent would linger in the air around the farm.

The vegetable plot could use a good spading, he thought to himself. It would soon be time for planting potatoes and cabbages. He took the narrow, square-bladed spade from the tool shed and began to dig, focused on turning over the moist brown dirt in even rows.

Behind him, Jack heard noises, like the soft whinnying he was so familiar with. He jerked upright and turned around, letting the spade fall to the ground. There they were, the whole herd, it looked like, filling the sky with their black wings. The thestrals in the vanguard were already alighting softly to earth, their hooves scarcely rippling the grass.

Overjoyed and relieved beyond measure, Jack ran up to the closest thestrals, as more and more landed, and the crowd of animals on the ground grew ever larger. He reached up and threw his arms around the neck of one of them, at least as high as he could do, given their stature. The thestral did not shy away. There was a bond of affection between Jack and them � he was not repelled by their wraithlike looks, and they did not flinch at his touch.

But the thestrals were obviously attracted by the food troughs, and they all surrounded them to begin eating, including the beast that Jack had embraced. As it pulled away from his arms to find its place at the trough, Jack saw that his arms and hands were smeared with some dark, gummy substance, foul-smelling and repulsive. He stared at it in amazement.

“Merlin’s beard!� he claimed. “Where have you been? What have you been doing? What is this stuff?� But the thestrals, greedily gulping their meal, did not give an answer, and Jack did not expect one. Although he often spoke to them, they never replied.

After he cleaned himself up, he thought, he would have to write another letter. He would have to inspect all the thestrals to ensure that they were not hurt in any way, and (his heart sank at the thought of it) to see how many of them were coated in that gummy stuff. He prayed that Scourgify would prove sufficient to wash it off.

His own brown owl had returned a while previously, bearing no return message, which he had thought odd at the time, given the contents of the letter he had sent. But now, as he stood on the grass in the sunlight, holding his dirty arms out in front of him, watching the thestrals eating, and contemplating the day’s astonishing events, a gray owl appeared out of the sky, flew up to him, and settled on one of his outstretched arms. Jack was startled out of his thoughts, and he walked over to the cottage, where the gray owl hopped off his arm and onto a railing, obviously pleased to distance itself from the rank smell on Jack’s sleeves.

Trying not to contaminate the owl’s feathers with the substance on his hands, Jack delicately unfastened the parchment scroll from the leg of the gray owl, which promptly flew away without even waiting for Jack to fetch it an owl treat.

Jack unrolled the parchment and read the message. But it was not the scolding he had expected to receive for his temporary loss of his herd of thestrals. It was amazing news, unbelievable news, completely undreamed-of news, news that He-Who-Must-Not-Be-Named was finally dead and their nightmare was over.

Jack read the message over and over, hardly able to wrap his mind around it, but finally he lifted his head from the parchment and gazed at the thestrals, eating away as if nothing special had happened, as if this day were like any other.

“Is that where you were?� he whispered. “Is that what you did?�