Fawkes's song gently trailed off into nothing.

Harry sat up from where he had lain on the winter-blasted grass, Fawkes still perched on his shoulder.

There were intakes of breath from all around him.

"Harry," said Seamus in a wavering voice, "are you all right?"

The peace of the phoenix was still in him, and warmth, from where Fawkes perched. Warmth, spreading out through him, and the memory of the song, still alive in the phoenix's presence. There were terrible things that had happened to him, terrible thoughts that had passed through him. He had regained an impossible memory, for all that the Dementor had made him desecrate it. A strange word kept echoing in his mind. And all of that could be put on hold for later, while the phoenix still shone red and gold beneath the setting sun.

Fawkes cawed at him.

"Something I have to do?" Harry said to Fawkes. "What?"

Fawkes bobbed its head in the direction of the Dementor.

Harry looked at the unseeable horror still in its cage, then back at the phoenix, puzzled.

"Mr. Potter?" said Minerva McGonagall's voice from behind him. "Are you all right?"

Harry climbed to his feet and turned.

Minerva McGonagall was looking at him, looking very worried; Albus Dumbledore beside her was studying him carefully; Filius Flitwick appeared tremendously relieved; and all the students were just plain staring.

"I think so, Professor McGonagall," Harry said calmly. He'd almost said Minerva before managing to stop himself. While Fawkes was on his shoulder, at least, Harry was fine; it might be that he would collapse a moment after Fawkes left, but somehow thoughts like that didn't seem important. "I think I'm okay."

There ought to have been cheering, or sighs of relief, or something, but no one seemed to know what to say, no one at all.

The peace of the phoenix lingered.

Harry turned back. "Hermione?" he said.

Everyone with the tiniest smidgin of romance in their hearts held their breath.

"I don't really know how to say thank you graciously," Harry said quietly, "any more than I know how to apologize. All I can say that if you're wondering whether it was the right thing to do, it was."

The boy and the girl gazed into each other's eyes.

"Sorry," Harry said. "About what happens next. If there's anything I can do -"

"No," Hermione said back. "There isn't. It's all right, though." Then she turned from Harry and walked away, toward the path that led back to the gates of Hogwarts.

A number of girls gave Harry puzzled looks, and then followed her. As they went, you could hear the excited questions starting.

Harry looked at them as they left, turned back to look at the other students. They'd seen him on the ground, screaming, and...

Fawkes nuzzled his cheek, briefly.

...and that would help them, someday, understanding that the Boy-Who-Lived could also be hurt, could be wretched. So that when they were hurt and wretched themselves, they would remember seeing Harry writhing on the ground, and know that their own pain and troubles didn't mean they'd never amount to anything. Had the Headmaster calculated that, when he had let the other students stay and watch?

Harry's eyes went back to the tall tattered cloak, almost absentmindedly, and without really being aware of what he was speaking, Harry said, "It shouldn't ought to exist."

"Ah," said a dry, precise voice. "I thought you might say that. I am very sorry to tell you, Mr. Potter, that Dementors cannot be killed. Many have tried."

"Really?" Harry said, still absentmindedly. "What did they try?"

"There is a certain extremely dangerous and destructive spell," Professor Quirrell said, "which I will not name here; a spell of cursed fire. It is what you would use to destroy an ancient device such as the Sorting Hat. It has no effect on Dementors. They are undying."

"They are not undying," said the Headmaster. The words mild, the gaze sharp. "They do not possess eternal life. They are wounds in the world, and attacking a wound only makes it larger."

"Hm," Harry said. "Suppose you threw it into the Sun? Would it be destroyed?"

"Throw it into the Sun?" squeaked Professor Flitwick, looking like he wanted to faint.

"It seems unlikely, Mr. Potter," Professor Quirrell said dryly. "The Sun is very large, after all; I doubt the Dementor would have much effect on it. But it is not a test I would like to try, Mr. Potter, just in case."

"I see," Harry said.

Fawkes cawed a final time, mantled his wings around Harry's head, and then launched himself from Harry. Launched himself straight toward the Dementor, screaming a great piercing cry of defiance that echoed around the field. And before anyone could react to that, there was a flash of fire, and Fawkes was gone.

The peace faded, a little.

The warmth faded, a little.

Harry took in a deep breath, let it out again.

"Yep," Harry said. "Still alive."

Again that silence, again the absence of cheering; no one seemed to know how to respond -

"It is good to know you are fully recovered, Mr. Potter," Professor Quirrell said firmly, as though to deny any other possibility. "Now, I believe Miss Ransom was up next?"

That started a bit of an argument, in which Professor Quirrell was right and everyone else was wrong. The Defense Professor pointed out that, despite the understandable emotions of all concerned, the chance of a similar mishap occurring to any other student verged on the infinitesimal; the more so as they now knew to avoid mischances with wands. And meanwhile, there were other students who needed to take their own best chance at casting a corporeal Patronus Charm, or else learn the feeling of a Dementor so they could flee, and discover their own degree of vulnerability...

In the end it turned out that Dean Thomas and Ron Weasley of Gryffindor were the only ones left who were still willing to go anywhere near the Dementor, which simplified the argument.

Harry glanced in the Dementor's direction. The word echoed in his mind again.

All right, Harry thought to himself, if the Dementor is a riddle, what is the answer?

And just like that, it was obvious.

Harry looked at the tarnished, slightly corroded cage.

He saw what lay beneath the tall, tattered cloak.

That was it, then.

Professor McGonagall came and spoke to Harry. She hadn't seen the worst of it, so there was only a slight glitter of water in her eyes. Harry told her that he needed to talk to her afterward and ask a question he'd put off for a while, but that didn't need to happen right now, if she was busy. There was a certain look about her which suggested that she had been pulled away from something important; and Harry observed this to her, and said that she honestly didn't need to feel guilty about leaving. This earned him something of a sharp look, but then leave she did, hurriedly, with a promise that they would talk later.

Dean Thomas cast his white bear again, even in the Dementor's presence; and Ron Weasley put up an adequate shield of sparkling mist. Which concluded the day, so far as everyone else was concerned, and Professor Flitwick began to herd the students back to Hogwarts. When it was clear that Harry meant to stay behind, Professor Flitwick looked at him quizzically; and Harry, for his part, glanced significantly at Dumbledore. Harry didn't know what Professor Flitwick made of that, but after a sharp gaze of warning, his Head of House departed.

And so remained only Harry, Professor Quirrell, Headmaster Dumbledore, and an Auror trio.

It would have been better to get rid of the trio first, but Harry couldn't think of a good way to do that.

"All right," said Auror Komodo, "let's take it back."

"Excuse me," Harry said. "I'd like to have another go at the Dementor."

Harry's request met with a certain amount of opposition of the you're completely insane variety, though it was only Auror Butnaru who actually said that out loud.

"Fawkes told me to," Harry said.

This did not overcome all the opposition, despite the look of shock it produced on Dumbledore's face. The argument went on, and it was starting to wear the edges off the phoenix's remaining peace, which annoyed Harry, though only a little.

"Look," Harry said, "I'm pretty sure I know what I was doing wrong before. There's a kind of person who has to use a different sort of warm and happy thought. Just let me try it, okay?"

This did not prove persuasive either.

"I think," Professor Quirrell said finally, staring at Harry with narrowed eyes, "that if we do not allow him to do this under supervision, he may, at some point or another, sneak off and look for a Dementor on his own. Do I accuse you falsely, Mr. Potter?"

There was an appalled pause at this. It seemed like a good time to play his trump card.

"I don't mind if the Headmaster keeps his own Patronus up," Harry said. For I will be in the presence of a Dementor just the same, Patronus or no.

There was confusion at this, even Professor Quirrell looked puzzled; but the Headmaster finally acceded, since it didn't seem likely that Harry could be hurt through four Patronuses.

If the Dementor could not reach through your Patronus on some level, Albus Dumbledore, you would not see a naked man painful to look upon...

Harry didn't say it out loud, for obvious reasons.

And they began to walk toward the Dementor.

"Headmaster," Harry said, "suppose the Ravenclaw door asked you this riddle: What lies at the center of a Dementor? What would you say?"

"Fear," said the Headmaster.

It was a simple enough mistake. The Dementor approached, and the fear came over you. The fear hurt, you felt the fear weakening you, you wanted the fear to go away.

It was natural to think the fear was the problem.

So they'd concluded that the Dementor was a creature of pure fear, that there was nothing there to fear but fear itself, that the Dementor couldn't hurt you if you weren't afraid...

But...

What lies at the center of a Dementor?

Fear.

What is so horrible that the mind refuses to see it?

Fear.

What is impossible to kill?

Fear.

...it didn't quite fit, once you thought about it.

Though it was clear enough why people would be reluctant to look beyond the first answer.

People understood fear.

People knew what they were supposed to do about fear.

So, faced with a Dementor, it wouldn't exactly be comforting to ask: 'What if the fear is just a side effect rather than the main problem?'

They had come very close to the Dementor's cage guarded by four Patronuses, when there came sharp intakes of breath from the three Aurors and Professor Quirrell. Everyone's faces turned to look at the Dementor, seeming to listen; there was horror on Auror Goryanof's face.

Then Professor Quirrell raised his head, his face hard, and spat toward the Dementor.

"It did not like having its prey taken from it, I suppose," Dumbledore said quietly. "Well. If it becomes necessary, Quirinus, there will always be a refuge for you at Hogwarts."

"What did it say?" said Harry.

Every head swung to stare at him.

"You didn't hear it...?" Dumbledore said.

Harry shook his head.

"It said to me," said Professor Quirrell, "that it knew me, and that it would hunt me down someday, wherever I tried to hide." His face was rigid, showing no fright.

"Ah," Harry said. "I wouldn't worry about that, Professor Quirrell." It's not like Dementors can actually talk, or think; the structure they have is borrowed from your own mind and expectations...

Now everyone was giving him very strange looks. The Aurors were glancing nervously at each other, at the Dementor, at Harry.

And they stood directly before the Dementor's cage.

"They are wounds in the world," Harry said. "It's just a wild guess, but I'm guessing the one who said that was Godric Gryffindor."

"Yes..." said Dumbledore. "How did you know?"

It is a common misconception, thought Harry, that all the best rationalists are Sorted into Ravenclaw, leaving none for other Houses. This is not so; being Sorted into Ravenclaw indicates that your strongest virtue is curiosity, wondering and desiring to know the true answer. And this is not the only virtue a rationalist needs. Sometimes you have to work hard on a problem, and stick to it for a while. Sometimes you need a clever plan for finding out. And sometimes what you need more than anything else to see an answer, is the courage to face it...

Harry's gaze went to what lay beneath the cloak, the horror far worse than any decaying mummy. Rowena Ravenclaw might also have known, for it was an obvious enough riddle once you saw it as a riddle.

And it was also obvious why the Patronuses were animals. The animals didn't know, and so were sheltered from the fear.

But Harry knew, and would always know, and would never be able to forget. He'd tried to teach himself to face reality without flinching, and though Harry had not yet mastered that art, still those grooves had been worn into his mind, the learned reflex to look toward the painful thought instead of away. Harry would never be able to forget by thinking warm happy thoughts about something else, and that was why the spell hadn't worked for him.

So Harry would think a warm happy thought that wasn't about something else.

Harry drew forth his wand that Professor Flitwick had returned to him, put his feet into the beginning stance for the Patronus Charm.

Within his mind, Harry discarded the last remnants of the peace of the phoenix, put aside the calm, the dreamlike state, remembered instead Fawkes's piercing cry, and roused himself for battle. Called upon all the pieces and elements of himself to awaken. Raised up within himself all the strength that the Patronus Charm could ever draw upon, to put himself into the right frame of mind for the final warm and happy thought; remembered all bright things.

The books his father had bought him.

Mum's smile when Harry had handmade her a mother's day card, an elaborate thing that had used half a pound of spare electronics parts from the garage to flash lights and beep a little tune, and had taken him three days to make.

Professor McGonagall telling him that his parents had died well, protecting him. As they had.

Realizing that Hermione was keeping up with him and even running faster, that they could be true rivals and friends.

Coaxing Draco out of the darkness, watching him slowly move toward the light.

Neville and Seamus and Lavender and Dean and everyone else who looked up to him, everyone that he would have fought to protect if anything threatened Hogwarts.

Everything that made life worth living.

His wand rose into the starting position for the Patronus Charm.

Harry thought of the stars, the image that had almost held off the Dementor even without a Patronus. Only this time, Harry added the missing ingredient, he'd never truly seen it but he'd seen the pictures and the video. The Earth, blazing blue and white with reflected sunlight as it hung in space, amid the black void and the brilliant points of light. It belonged there, within that image, because it was what gave everything else its meaning. The Earth was what made the stars significant, made them more than uncontrolled fusion reactions, because it was Earth that would someday colonize the galaxy, and fulfill the promise of the night sky.

Would they still be plagued by Dementors, the children's children's children, the distant descendants of humankind as they strode from star to star? No. Of course not. The Dementors were only little nuisances, paling into nothingness in the light of that promise; not unkillable, not invincible, not even close. You had to put up with little nuisances, if you were one of the lucky and unlucky few to be born on Earth; on Ancient Earth, as it would be remembered someday. That too was part of what it meant to be alive, if you were one of the tiny handful of sentient beings born into the beginning of all things, before intelligent life had come fully into its power. That the much vaster future depended on what you did here, now, in the earliest days of dawn, when there was still so much darkness to be fought, and temporary nuisances like Dementors.

Mum and Dad, Hermione's friendship and Draco's journey, Neville and Seamus and Lavender and Dean, the blue sky and brilliant Sun and all bright things, the Earth, the stars, the promise, everything humanity was and everything it would become...

On the wand, Harry's fingers moved into their starting positions; he was ready, now, to think the right sort of warm and happy thought.

And Harry's eyes stared directly at that which lay beneath the tattered cloak, looked straight at that which had been named Dementor. The void, the emptiness, the hole in the universe, the absence of color and space, the open drain through which warmth poured out of the world.

The fear it exuded stole away all happy thoughts, its closeness drained your power and strength, its kiss would destroy everything that you were.

I know you now, Harry thought as his wand twitched once, twice, thrice and four times, as his fingers slid exactly the right distances, I comprehend your nature, you symbolize Death, through some law of magic you are a shadow that Death casts into the world.

And Death is not something I will ever embrace.

It is only a childish thing, that the human species has not yet outgrown.

And someday...

We'll get over it...

And people won't have to say goodbye any more...

The wand rose up and leveled straight at the Dementor.

"EXPECTO PATRONUM!"

The thought exploded from him like a breaking dam, surged down his arm into his wand, burst from it as blazing white light. Light that became corporeal, took on shape and substance.

A figure with two arms, two legs, and a head, standing upright; the animal Homo sapiens, the shape of a human being.

Glowing brighter and brighter as Harry poured all his strength into his spell, blazing with incandescent light brighter than the fading sunset, the Aurors and Professor Quirrell shielding their eyes in shock -

And someday when the descendants of humanity have spread from star to star, they won't tell the children about the history of Ancient Earth until they're old enough to bear it; and when they learn they'll weep to hear that such a thing as Death had ever once existed!

The figure of a human shone more brilliant now than the noonday Sun, so radiant that Harry could feel the warmth of it on his skin; and Harry sent out all his defiance at the shadow of Death, opening all the floodgates inside him to make that bright shape blaze even brighter and yet brighter.

You are not invincible, and someday the human species will end you.

I will end you if I can, by the power of mind and magic and science.

I won't cower in fear of Death, not while I have a chance of winning.

I won't let Death touch me, I won't let Death touch the ones I love.

And even if you do end me before I end you,

Another will take my place, and another,

Until the wound in the world is healed at last...

Harry lowered his wand, and the bright figure of a human faded away.

Slowly, he exhaled.

Like waking up from a dream, like opening his eyes after sleep, Harry's gaze moved away from the cage, he looked around and saw that everyone was staring at him.

Albus Dumbledore was staring at him.

Professor Quirrell was staring at him.

The Auror trio was staring at him.

They were all looking at him like they'd just seen him destroy a Dementor.

The tattered cloak lay empty within the cage.