“He took my blood,” said Harry.
“Precisely!” said Dumbledore. “He took your blood and rebuilt his living body with it! Your blood in his veins, Harry, Lily’s protection inside both of you! He tethered you to life while he lives!”
“I live . . . while he lives? But I thought . . . I thought it was the other way round! I thought we both had to die? Or is it the same thing?”
He was distracted by the whimpering and thumping of the agonized creature behind them and glanced back at it yet again.
“Are you sure we can’t do anything?”
“There is no help possible.”
“Then explain . . . more,” said Harry, and Dumbledore smiled.
“You were the seventh Horcrux, Harry, the Horcrux he never meant to make. He had rendered his soul so unstable that it broke apart when he committed those acts of unspeakable evil, the murder of your parents, the attempted killing of a child. But what escaped from that room was even less than he knew. He left more than his body behind. He left part of himself latched to you, the would-be victim who had survived.
“And his knowledge remained woefully incomplete, Harry! That which Voldemort does not value, he takes no trouble to comprehend. Of house-elves and children’s tales, of love, loyalty, and innocence, Voldemort knows and understands nothing. Nothing. That they all have a power beyond his own, a power beyond the reach of any magic, is a truth he has never grasped.
“He took your blood believing it would strengthen him. He took into his body a tiny part of the enchantment your mother laid upon you when she died for you. His body keeps her sacrifice alive, and while that enchantment survives, so do you and so does Voldemort’s one last hope for himself.”
Dumbledore smiled at Harry, and Harry stared at him.
“And you knew this? You knew — all along?”
“I guessed. But my guesses have usually been good,” said Dumbledore happily, and they sat in silence for what seemed like a long time, while the creature behind them continued to whimper and tremble.
“There’s more,” said Harry. “There’s more to it. Why did my wand break the wand he borrowed?”
“As to that, I cannot be sure.”
“Have a guess, then,” said Harry, and Dumbledore laughed.
“What you must understand, Harry, is that you and Lord Voldemort have journeyed together into realms of magic hitherto unknown and untested. But here is what I think happened, and it is unprecedented, and no wandmaker could, I think, ever have predicted it or explained it to Voldemort.
“Without meaning to, as you now know, Lord Voldemort doubled the bond between you when he returned to a human form. A part of his soul was still attached to yours, and, thinking to strengthen himself, he took a part of your mother’s sacrifice into himself. If he could only have understood the precise and terrible power of that sacrifice, he would not, perhaps, have dared to touch your blood. . . . But then, if he had been able to understand, he could not be Lord Voldemort, and might never have murdered at all.
“Having ensured this two-fold connection, having wrapped your destinies together more securely than ever two wizards were joined in history, Voldemort proceeded to attack you with a wand that shared a core with yours. And now something very strange happened, as we know. The cores reacted in a way that Lord Voldemort, who never knew that your wand was twin of his, had never expected.
“He was more afraid than you were that night, Harry. You had accepted, even embraced, the possibility of death, something Lord Voldemort has never been able to do. Your courage won, your wand overpowered his. And in doing so, something happened between those wands, something that echoed the relationship between their masters.
“I believe that your wand imbibed some of the power and qualities of Voldemort’s wand that night, which is to say that it contained a little of Voldemort himself. So your wand recognized him when he pursued you, recognized a man who was both kin and mortal enemy, and it regurgitated some of his own magic against him, magic much more powerful than anything Lucius’s wand had ever performed. Your wand now contained the power of your enormous courage and of Voldemort’s own deadly skill: What chance did that poor stick of Lucius Malfoy’s stand?”
“But if my wand was so powerful, how come Hermione was able to break it?” asked Harry.
“My dear boy, its remarkable effects were directed only at Voldemort, who had tampered so ill-advisedly with the deepest laws of magic. Only toward him was that wand abnormally powerful. Otherwise it was a wand like any other . . . though a good one, I am sure,” Dumbledore finished kindly.
Harry sat in thought for a long time, or perhaps seconds. It was very hard to be sure of things like time, here.
“He killed me with your wand.”
“He failed to kill you with my wand,” Dumbledore corrected Harry. “I think we can agree that you are not dead — though, of course,” he added, as if fearing he had been discourteous, “I do not minimize your sufferings, which I am sure were severe.”
“I feel great at the moment, though,” said Harry, looking down at his clean, unblemished hands. “Where are we, exactly?”
“Well, I was going to ask you that,” said Dumbledore, looking around. “Where would you say that we are?”
Until Dumbledore had asked, Harry had not known. Now, however, he found that he had an answer ready to give.
“It looks,” he said slowly, “like King’s Cross station. Except a lot cleaner and empty, and there are no trains as far as I can see.”
“King’s Cross station!” Dumbledore was chuckling immoderately. “Good gracious, really?”
“Well, where do you think we are?” asked Harry, a little defensively.
“My dear boy, I have no idea. This is, as they say, your party.”