Harry Potter and the Half-Blood Prince

“Think!” said Snape, impatient again. “Think! By waiting two hours, just two hours, I ensured that I could remain at Hogwarts as a spy! By allowing Dumbledore to think that I was only returning to the Dark Lord’s side because I was ordered to, I have been able to pass information on Dumbledore and the Order of the Phoenix ever since! Consider, Bellatrix: The Dark Mark had been growing stronger for months. I knew he must be about to return, all the Death Eaters knew! I had plenty of time to think about what I wanted to do, to plan my next move, to escape like Karkaroff, didn’t I?

“The Dark Lord’s initial displeasure at my lateness vanished entirely, I assure you, when I explained that I remained faithful, although Dumbledore thought I was his man. Yes, the Dark Lord thought that I had left him forever, but he was wrong.”

“But what use have you been?” sneered Bellatrix. “What useful information have we had from you?”

“My information has been conveyed directly to the Dark Lord,” said Snape. “If he chooses not to share it with you—”

“He shares everything with me!” said Bellatrix, firing up at once. “He calls me his most loyal, his most faithful—”

“Does he?” said Snape, his voice delicately inflected to suggest his disbelief. “Does he still, after the fiasco at the Ministry?”

“That was not my fault!” said Bellatrix, flushing. “The Dark Lord has, in the past, entrusted me with his most precious—if Lucius hadn’t—”

“Don’t you dare—don’t you dare blame my husband!” said Narcissa, in a low and deadly voice, looking up at her sister.

“There is no point apportioning blame,” said Snape smoothly. “What is done, is done.”

“But not by you!” said Bellatrix furiously. “No, you were once again absent while the rest of us ran dangers, were you not, Snape?”

“My orders were to remain behind,” said Snape. “Perhaps you disagree with the Dark Lord, perhaps you think that Dumbledore would not have noticed if I had joined forces with the Death Eaters to fight the Order of the Phoenix? And—forgive me—you speak of dangers… you were facing six teenagers, were you not?”

“They were joined, as you very well know, by half of the Order before long!” snarled Bellatrix. “And, while we are on the subject of the Order, you still claim you cannot reveal the whereabouts of their headquarters, don’t you?”

“I am not the Secret-Keeper; I cannot speak the name of the place. You understand how the enchantment works, I think? The Dark Lord is satisfied with the information I have passed him on the Order. It led, as perhaps you have guessed, to the recent capture and murder of Emmeline Vance, and it certainly helped dispose of Sirius Black, though I give you full credit for finishing him off.”

He inclined his head and toasted her. Her expression did nor soften.

“You are avoiding my last question, Snape. Harry Potter. You could have killed him at any point in the past five years. You have not done it. Why?”

“Have you discussed this matter with the Dark Lord?” asked Snape.

“He… lately, we… I am asking you, Snape!”

“If I had murdered Harry Potter, the Dark Lord could not have used his blood to regenerate, making him invincible—”

“You claim you foresaw his use of the boy!” she jeered.

“I do not claim it; I had no idea of his plans; I have already confessed that I thought the Dark Lord dead. I am merely trying to explain why the Dark Lord is not sorry that Potter survived, at least until a year ago…”

“But why did you keep him alive?”

“Have you not understood me? It was only Dumbledore’s protection that was keeping me out of Azkaban! Do you disagree that murdering his favorite student might have turned him against me? But there was more to it than that. I should remind you that when Potter first arrived at Hogwarts there were still many stories circulating about him, rumors that he himself was a great Dark wizard, which was how he had survived the Dark Lord’s attack. Indeed, many of the Dark Lords old followers thought Potter might be a standard around which we could all rally once more. I was curious, I admit it, and not at all inclined to murder him the moment he set fool in the castle.

“Of course, it became apparent to me very quickly that he had no extraordinary talent at all. He has fought his way out of a number of tight corners by a simple combination of sheer luck and more talented friends. He is mediocre to the last degree, though as obnoxious and self-satisfied as was his father before him. I have done my utmost to have him thrown out of Hogwarts, where I believe he scarcely belongs, but kill him, or allow him to be killed in front of me? I would have been a fool to risk it with Dumbledore close at hand.”

“And through all this we are supposed to believe Dumbledore has never suspected you?” asked Bellatrix. “He has no idea of your true allegiance, he trusts you implicitly still?”