Harry hesitated, then walked slowly across the room now littered with silver cogs and fragments of wood, and took the seat facing Dumbledore's desk.

'Am I to understand,' said Phineas Nigellus slowly from Harry's left, 'that my great-great-grandson — the last of the Blacks — is dead?'

'Yes, Phineas,' said Dumbledore.

'I don't believe it,' said Phineas brusquely.

Harry turned his head in time to see Phineas marching out of his portrait and knew that he had gone to visit his other painting in Grimmauld Place. He would walk, perhaps, from portrait to portrait, calling for Sirius through the house . . .

'Harry, I owe you an explanation,' said Dumbledore. 'An explanation of an old man's mistakes. For I see now that what I have done, and not done, with regard to you, bears all the hallmarks of the failings of age. Youth cannot know how age thinks and feels. But old men are guilty if they forget what it was to be young . . . and I seem to have forgotten, lately . . .'

The sun was rising properly now; there was a rim of dazzling orange visible over the mountains and the sky above it was colourless and bright. The light fell upon Dumbledore, upon the silver of his eyebrows and beard, upon the lines gouged deeply into his lace.

'I guessed, fifteen years ago,' said Dumbledore, 'when I saw the scar on your forehead, what it might mean. I guessed that it might be the sign of a connection forged between you and Voldemort.'

'You've told me this before, Professor,' said Harry bluntly. He did not care about being rude. He did not care about anything very much any more.

'Yes,' said Dumbledore apologetically. 'Yes, but you see — it is necessary to start with your scar. For it became apparent, shortly after you rejoined the magical world, that I was correct, and that your scar was giving you warnings when Voldemort was close to you, or else feeling powerful emotion.'

'I know,' said Harry wearily.

'And this ability of yours — to detect Voldemort's presence, even when he is disguised, and to know what he is feeling when his emotions are roused — has become more and more pronounced since Voldemort returned to his own body and his full powers.'

Harry did not bother to nod. He knew all of this already.

'More recently,' said Dumbledore, 'I became concerned that Voldemort might realise that this connection between you exists. Sure enough, there came a time when you entered so far into his mind and thoughts that he sensed your presence. I am speaking, of course, of the night when you witnessed the attack on Mr Weasley.'

'Yeah, Snape told me,' Harry muttered.

'Professor Snape, Harry,' Dumbledore corrected him quietly. 'But did you not wonder why it was not I who explained this to you? Why I did not teach you Occlumency? Why I had not so much as looked at you for months?'

Harry looked up. He could see now that Dumbledore looked sad and tired.

'Yeah,' Harry mumbled. 'Yeah, I wondered.'

'You see,' Dumbledore continued, 'I believed it could not be long before Voldemort attempted to force his way into your mind, to manipulate and misdirect your thoughts, and I was not eager to give him more incentives to do so. I was sure that if he realised that our relationship was — or had ever been — closer than that of headmaster and pupil, he would seize his chance to use you as a means to spy on me. I feared the uses to which he would put you, the possibility that he might try and possess you. Harry, I believe I was right to think that Voldemort would have made use of you in such a way. On those rare occasions when we had close contact, I thought I saw a shadow of him stir behind your eyes . . .'

Harry remembered the feeling that a dormant snake had risen in him, ready to strike, in those moments when he and Dumbledore had made eye-contact.

'Voldemort's aim in possessing you, as he demonstrated tonight, would not have been my destruction. It would have been yours. He hoped, when he possessed you briefly a short while ago, that I would sacrifice you in the hope of killing him. So you see, I have been trying, in distancing myself from you, to protect you, Harry. An old man s mistake . . .'

He sighed deeply. Harry was letting the words wash over him. He would have been so interested to know all this a few months ago, but now it was meaningless compared to the gaping chasm inside him that was the loss of Sirius; none of it mattered . . .

'Sirius told me you felt Voldemort awake inside you the very night that you had the vision of Arthur Weasley's attack. I knew at once that my worst fears were correct: Voldemort had realised he could use you. In an attempt to arm you against Voldemort's assaults on your mind, I arranged Occlumency lessons with Professor Snape.'

He paused. Harry watched the sunlight, which was sliding slowly across the polished surface of Dumbledore's desk, illuminate a silver ink pot and a handsome scarlet quill. Harry could tell that the portraits all around them were awake and listening raptly to Dumbledore's explanation; he could hear the occasional rustle of robes, the slight clearing of a throat. Phineas Nigellus had still not returned . . .

'Professor Snape discovered,' Dumbledore resumed, 'that you had been dreaming about the door to the Department of Mysteries for months. Voldemort, of course, had been obsessed with the possibility of hearing the prophecy ever since he regained his body; and as he dwelled on the door, so did you, though you did not know what it meant.

'And then you saw Rookwood, who worked in the Department of Mysteries before his arrest, telling Voldemort what we had known all along — that the prophecies held in the Ministry of Magic are heavily protected. Only the people to whom they refer can lift them from the shelves without suffering madness: in this case, either Voldemort himself would have to enter the Ministry of Magic, and risk revealing himself at last — or else you would have to take it for him. It became a matter of even greater urgency that you should master Occlumency.'

'But I didn't,' muttered Harry. He said it aloud to try and ease the dead weight of guilt inside him: a confession must surely relieve some of the terrible pressure squeezing his heart. 'I didn't practise, I didn't bother, I could've stopped myself having those dreams, Hermione kept telling me to do it, if I had he'd never have been able to show me where to go, and — Sirius wouldn't — Sirius wouldn't — '

Something was erupting inside Harry's head: a need to justify himself, to explain —

'I tried to check he'd really taken Sirius, I went to Umbridge's office, I spoke to Kreacher in the fire and he said Sirius wasn't there, he said he'd gone!'

'Kreacher lied,' said Dumbledore calmly. 'You are not his master, he could lie to you without even needing to punish himself. Kreacher intended you to go to the Ministry of Magic.'

'He — he sent me on purpose?'

'Oh yes. Kreacher, I am afraid, has been serving more than one master for months.'

'How?' said Harry blankly. 'He hasn't been out of Grimmauld Place for years.'

'Kreacher seized his opportunity shortly before Christmas,' said Dumbledore, 'when Sirius, apparently, shouted at him to "get out". He took Sirius at his word, and interpreted this as an order to leave the house. He went to the only Black family member for whom he had any respect left . . . Black's cousin Narcissa, sister of Bellatrix and wife of Lucius Malfoy.'

'How do you know all this?' Harry said. His heart was beating very fast. He felt sick. He remembered worrying about Kreacher's odd absence over Christmas, remembered him turning up again in the attic . . .

'Kreacher told me last night,' said Dumbledore. 'You see, when you gave Professor Snape that cryptic warning, he realised that you had had a vision of Sirius trapped in the bowels of the Department of Mysteries. He, like you, attempted to contact Sirius at once. I should explain that members of the Order of the Phoenix have more reliable methods of communicating than the fire in Dolores Umbridge's office. Professor Snape found that Sirius was alive and safe in Grimmauld Place.

'When, however, you did not return from your trip into the Forest with Dolores Umbridge, Professor Snape grew worried that you still believed Sirius to be a captive of Lord Voldemort's. He alerted certain Order members at once.'

Dumbledore heaved a great sigh and continued, 'Alastor Moody, Nymphadora Tonks, Kingsley Shacklebolt and Remus Lupin were at Headquarters when he made contact. All agreed to go to your aid at once. Professor Snape requested that Sirius remain behind, as he needed somebody to remain at Headquarters to tell me what had happened, for I was due there at any moment. In the meantime he, Professor Snape, intended to search the Forest for you.

'But Sirius did not wish to remain behind while the others went to search for you. He delegated to Kreacher the task of telling me what had happened. And so it was that when I arrived in Grimmauld Place shortly after they had all left for the Ministry, it was the elf who told me — laughing fit to burst — where Sirius had gone.'

'He was laughing?' said Harry in a hollow voice.

'Oh, yes,' said Dumbledore. 'You see, Kreacher was not able to betray us totally. He is not Secret Keeper for the Order, he could not give the Malfoy's our whereabouts, or tell them any of the Order's confidential plans that he had been forbidden to reveal. He was bound by the enchantments of his kind, which is to say that he could not disobey a direct order from his master, Sirius. But he gave Narcissa information of the sort that is very valuable to Voldemort, yet must have seemed much too trivial for Sirius to think of banning him from repeating it.'

'Like what?' said Harry.

'Like the fact that the person Sirius cared most about in the world was you,' said Dumbledore quietly. 'Like the fact that you were coming to regard Sirius as a mixture of father and brother. Voldemort knew already, of course, that Sirius was in the Order, and that you knew where he was — but Kreacher's information made him realise that the one person for whom you would go to any lengths to rescue was Sirius Black.'

Harry's lips were cold and numb.

'So . . . when I asked Kreacher if Sirius was there last night . . .'

'The Malfoy's — undoubtedly on Voldemort's instructions — had told him he must find a way of keeping Sirius out of the way once you had seen the vision of Sirius being tortured. Then, if you decided to check whether Sirius was at home or not, Kreacher would be able to pretend he was not. Kreacher injured Buckbeak the Hippogriff yesterday, and, at the moment when you made your appearance in the fire, Sirius was upstairs tending to him.'

There seemed to be very little air in Harry's lungs; his breathing was quick and shallow.