“And why may I not have the same information?”

“I prefer not to put all of my secrets in one basket, particularly not a basket that spends so much time dangling on the arm of Lord Voldemort.”

“Which I do on your orders!”

“And you do it extremely well. Do not think that I underestimate the constant danger in which you place yourself, Severus. To give Voldemort what appears to be valuable information while withholding the essentials is a job I would entrust to nobody but you.”

“Yet you confide much more in a boy who is incapable of Occlumency, whose magic is mediocre, and who has a direct connection into the Dark Lord’s mind!”

“Voldemort fears that connection,” said Dumbledore. “Not so long ago he had one small taste of what truly sharing Harry’s mind means to him. It was pain such as he has never experienced. He will not try to possess Harry again, I am sure of it. Not in that way.”

“I don’t understand.”

“Lord Voldemort’s soul, maimed as it is, cannot bear close contact with a soul like Harry’s. Like a tongue on frozen steel, like flesh in flame—”

“Souls? We were talking of minds!”

“In the case of Harry and Lord Voldemort, to speak of one is to speak of the other.”

Dumbledore glanced around to make sure that they were alone. They were close by the Forbidden Forest now, but there was no sign of anyone near them.

“After you have killed me, Severus—”

“You refuse to tell me everything, yet you expect that small service of me!” snarled Snape, and real anger flared in the thin face now. “You take a great deal for granted, Dumbledore! Perhaps I have changed my mind!”

“You gave me your word, Severus. And while we are talking about services you owe me, I thought you agreed to keep a close eye on our young Slytherin friend?”

Snape looked angry, mutinous. Dumbledore sighed.

“Come to my office tonight, Severus, at eleven, and you shall not complain that I have no confidence in you…”

They were back in Dumbledore’s office, the windows dark, and Fawkes sat silent as Snape sat quite still, as Dumbledore walked around him, talking.

“Harry must not know, not until the last moment, not until it is necessary, otherwise how could he have the strength to do what must be done?”

“But what must he do?”

“That is between Harry and me. Now listen closely, Severus. There will come a time—after my death—do not argue, do not interrupt! There will come a time when Lord Voldemort will seem to fear for the life of his snake.”

“For Nagini?” Snape looked astonished.

“Precisely. If there comes a time when Lord Voldemort stops sending that snake forth to do his bidding, but keeps it safe beside him under magical protection, then, I think, it will be safe to tell Harry.”

“Tell him what?”

Dumbledore took a deep breath and closed his eyes.

“Tell him that on the night Lord Voldemort tried to kill him, when Lily cast her own life between them as a shield, the Killing Curse rebounded upon Lord Voldemort, and a fragment of Voldemort’s soul was blasted apart from the whole, and latched itself onto the only living soul left in that collapsed building. Part of Lord Voldemort lives inside Harry, and it is that which gives him the power of speech with snakes, and a connection with Lord Voldemort’s mind that he has never understood. And while that fragment of soul, unmissed by Voldemort, remains attached to and protected by Harry, Lord Voldemort cannot die.”

Harry seemed to be watching the two men from one end of a long tunnel, they were so far away from him, their voices echoing strangely in his ears.

“So the boy… the boy must die?” asked Snape quite calmly.

“And Voldemort himself must do it, Severus. That is essential.”

Another long silence. Then Snape said, “I thought… all those years… that we were protecting him for her. For Lily.”

“We have protected him because it has been essential to teach him, to raise him, to let him try his strength,” said Dumbledore, his eyes still tight shut. “Meanwhile, the connection between them grows ever stronger, a parasitic growth. Sometimes I have thought he suspects it himself. If I know him, he will have arranged matters so that when he does set out to meet his death, it will truly mean the end of Voldemort.”

Dumbledore opened his eyes. Snape looked horrified.

“You have kept him alive so that he can die at the right moment?”

“Don’t be shocked, Severus. How many men and women have you watched die?”

“Lately, only those whom I could not save,” said Snape. He stood up. “You have used me.”

“Meaning?”

“I have spied for you and lied for you, put myself in mortal danger for you. Everything was supposed to be to keep Lily Potter’s son safe. Now you tell me you have been raising him like a pig for slaughter—”

“But this is touching, Severus,” said Dumbledore seriously. “Have you grown to care for the boy, after all?”

“For him?” shouted Snape. “Expecto Patronum!”

From the tip of his wand burst the silver doe. She landed on the office floor, bounded once across the office, and soared out of the window. Dumbledore watched her fly away, and as her silvery glow faded he turned back to Snape, and his eyes were full of tears.

“After all this time?”

“Always,” said Snape.

And the scene shifted. Now, Harry saw Snape talking to the portrait of Dumbledore behind his desk.

“You will have to give Voldemort the correct date of Harry’s departure from his aunt and uncle’s,” said Dumbledore. “Not to do so will raise suspicion, when Voldemort believes you so well informed. However, you must plant the idea of decoys; that, I think, ought to ensure Harry’s safety. Try Confunding Mundungus Fletcher. And Severus, if you are forced to take part in the chase, be sure to act your part convincingly… I am counting upon you to remain in Lord Voldemort’s good books as long as possible, or Hogwarts will be left to the mercy of the Carrows…”

Now Snape was head to head with Mundungus in an unfamiliar tavern, Mundungus’s face looking curiously blank, Snape frowning in concentration.

“You will suggest to the Order of the Phoenix,” Snape murmured, “that they use decoys. Polyjuice Potion. Identical Potters. It’s the only thing that might work. You will forget that I have suggested this. You will present it as your own idea. You understand?”

“I understand,” murmured Mundungus, his eyes unfocused…

Now Harry was flying alongside Snape on a broomstick through a clear dark night: He was accompanied by other hooded Death Eaters, and ahead were Lupin and a Harry who was really George… A Death Eater moved ahead of Snape and raised his wand, pointing it directly at Lupin’s back.

“Sectumsempra!” shouted Snape.

But the spell, intended for the Death Eater’s wand hand, missed and hit George instead—

And next, Snape was kneeling in Sirius’s old bedroom. Tears were dripping from the end of his hooked nose as he read the old letter from Lily. The second page carried only a few words:

Snape took the page bearing Lily’s signature, and her love, and tucked it inside his robes. Then he ripped in two the photograph he was also holding, so that he kept the part from which Lily laughed, throwing the portion showing James and Harry back onto the floor, under the chest of drawers…

And now Snape stood again in the headmaster’s study as Phineas Nigellus came hurrying into his portrait.

“Headmaster! They are camping in the Forest of Dean! The Mudblood—”

“Do not use that word!”

“—the Granger girl, then, mentioned the place as she opened her bag and I heard her!”

“Good. Very good!” cried the portrait of Dumbledore behind the headmaster’s chair. “Now, Severus, the sword! Do not forget that it must be taken under conditions of need and valor—and he must not know that you give it! If Voldemort should read Harry’s mind and see you acting for him—”