Harry Potter and the Half-Blood Prince
Chapter Two, Spinner's End

‘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 favourite 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, rumours that he himself was a great Dark wizard, which was how he had survived the Dark Lord’s attack. Indeed, many of the Dark Lord’s 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 foot 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?’

‘I have played my part well,’ said Snape. ‘And you overlook Dumbledore’s greatest weakness: he has to believe the best of people. I spun him a tale of deepest remorse when I joined his staff, fresh from my Death Eater days, and he embraced me with open arms ? though, as I say, never allowing me nearer the Dark Arts than he could help. Dumbledore has been a great wizard ? oh yes, he has’ (for Bellatrix had made a scathing noise) ‘the Dark Lord acknowledges it. I am pleased to say, however, that Dumbledore is growing old. The duel with the Dark Lord last month shook him. He has since sustained a serious injury because his reactions are slower than they once were. But through all these years, he has never stopped trusting Severus Snape, and therein lies my great value to the Dark Lord.’

Bellatrix still looked unhappy, though she appeared unsure how best to attack Snape next. Taking advantage of her silence, Snape turned to her sister.

‘Now … you came to ask me for help, Narcissa?’