The next day, Harry and Hermione moved out of the Room of Requirement; though what house they would be in was uncertain. Harry was sure that setting up a Sorting Ceremony was completely useless. He and Hermione were Gryffindors, weren't they? What else was there to say?

Dumbledore introduced them at breakfast, saying that they were students from another wizarding school who had come to Hogwarts for a trial period. Dumbledore had gone over none of this with Harry and Hermione, advising them only to pretend that they were cousins – to make it seem more believable, Harry thought. After Dumbledore had finished introducing them and they had sat down again, Harry thought he might have forgotten about the promised Sorting, but no. Harry reflected bitterly that Dumbledore never forgot anything, old though he was.

'And now, to initiate our two newest students,' said Dumbledore. He turned to Harry and Hermione. 'If you two would come here, please.' He waved his wand in the air and conjured a stool. 'Professor McGonagall, if you would …'

Professor McGonagall, who standing near Dumbledore as he talked, now produced a ragged brown hat from nowhere. She nodded at Hermione. 'You first, Miss Granger.' She gestured to the stool Dumbledore had conjured.

Hermione nodded, went over and sat down. Professor McGonagall put the Sorting Hat on her head as Harry and the rest of the school watched. Harry, who was sitting rather near the front of the room, could see Hermione's expression. First it went from reasonably calm to nervous, and then, for a split second, almost frightened. Then the hat shouted, 'GRYFFINDOR!' and Hermione gave the hat back to Professor McGonagall and joined Lily at the Gryffindor table.

'Your turn, Mr Potter,' said Professor McGonagall. There was an outbreak of whispering as Harry stood up, walked over to the hat and sat down on the stool. Professor McGonagall dropped the hat on his head.

Almost immediately, for the third time in his life, he heard a soft, whispering sort of voice that only he could hear come from the depths of the Sorting Hat.

'Ah, but haven't I Sorted you before?'

'Yes,' thought Harry, 'but that was later, wasn't it?'

'Time means nothing to me,' said the Hat. 'The fact remains – I have done you before, Mr Potter.'

'Yes, yes,' Harry thought desperately. 'And now why don't you just put me in the house you put me in last time?'

'You'll have to prove that you belong there,' said the voice. 'Heritage isn't everything, you know. As I have told you before, you are particularly difficult to Sort. Also, this is a different time. You yourself have changed, Harry Potter. Perhaps a different house will bring out the other side of you.'

Harry couldn't think of anything to reply to this.

'Ravenclaw, perhaps … there's some good common sense here – or maybe Hufflepuff? You are loyal – though, I admit, sometimes to the point of idiocy and delusion …'

'Just come on,' Harry thought. 'Hurry up, everybody's waiting …'

'Oh, all right,' said the Hat. Then it yelled, 'SLYTHERIN!'

Harry didn't move. 'I'm not a Slytherin!' he protested silently to the Hat.

'How do you know? You should have asked not to be one. If you are sure you are a Gryffindor, then I tell you to prove that you are not a Slytherin …' Then Professor McGonagall lifted the Hat off Harry's head and he got up, feeling dazed and resentful, and headed for the Slytherin table. He had to pay attention to where he was walking; he narrowly missed sitting at the Gryffindor one, where Hermione was gazing over at him, a puzzled look on her face.

'And now that that is over,' Dumbledore announced cheerily, 'I advise you to all finish your breakfast before it gets cold.' Then he sat down and began tucking into his breakfast, but at one point he glanced up and saw Harry watching him. Harry averted his eyes.

The Gryffindor table was right next to the Slytherin one. However, Harry and Hermione were so far apart that there was no chance of talking. Harry turned around towards his breakfast and found, to his annoyance, that he had sat down next to Snape. He glanced up just as the introductions started flowing.

'I'm Avery –'

'– Mulciber –'

'– Parkinson –'

'– and I'm Macnair, Walden Macnair.'

Harry nodded. The last name made him feel slightly sick – he'd heard it before, but he couldn't think where. He picked up a piece of toast but didn't eat; his experience with the Sorting Hat had taken away his appetite. It made him uncomfortable to think that he might actually be a Slytherin.

But hadn't the Sorting Hat put him in Gryffindor when he was eleven? And hadn't he already proved that he was a Gryffindor? And he'd asked Dumbledore about it at the end of his second year, and Dumbledore had told him that only a true Gryffindor could have pulled the Sword of Gryffindor out of the Sorting Hat.

He sat still, letting the conversation float over him and ignoring Snape completely. Voices came from the table opposite him: the Gryffindor one. He couldn't see the speaker's voice, but he could see his father (a thrill of delight exploded in his stomach) next to Peter Pettigrew, a small boy with a face like – Harry smirked – a rat. Then, opposite them, with their backs towards Harry, must be Sirius and Lupin. He could figure out who was speaking by craning his neck.

'… don't see why you don't just ask him,' Lupin was saying.

'I don't want to look like an idiot,' James said stubbornly. 'I mean – come on, Remus, he's a Slytherin!'

'What's that supposed to mean?' Lupin asked, with obviously feigned innocence. 'All you have to do is ask him.'

'Personally, I don't think you should bother,' interjected Sirius lazily. 'You're probably related – he looks rather like you, James.' With this, Harry realised they were talking about him.

'As if!' James broke out scornfully. 'My family have been in Gryffindor for years. It's probably just a coincidence – and I don't want to be related to any Slytherin. Having the same surname doesn't mean we're related.'

'Maybe you're estranged?' suggested Lupin, sounding as if he did not care, but was just keeping up the conversation for his friend's sake. James looked slightly appeased.

'Maybe,' he said carelessly. 'But I also want to know where he got that scar on his forehead. Can't you see it from here?'

Sirius and Lupin shook their heads, but Peter nodded eagerly, looking at James with some kind of worshipful fascination. James ignored him – rather superciliously, Harry thought.

'A curse scar, probably,' James added. 'It's shaped like a lightning bolt.' Then, very abruptly, he changed the subject. 'Wonder why he was hanging out with that Granger girl. Anyone can see they're not cousins.'

'How do you know?' asked Peter. He was still looking at James almost in adoration.

'Because they don't look anything alike,' James answered impatiently. 'I mean, look at them.' He gestured first towards Hermione, who was further up the Gryffindor table, then to Harry, who had stopped wondering about the Sorting fiasco to listen. 'She's got bushy brown hair, brown eyes and big teeth (reminds me of Evans a bit, somehow) – whereas he's got black hair, green eyes – and that scar, I suppose –'

'But that doesn't mean anything,' Sirius interrupted. 'I don't look anything like any of my cousins, either. Come off it, James! Why are you so obsessed with them, anyway?'

'I'm not obsessed! Just saying that, if they were cousins, they'd likely be in the same house!'

'That still doesn't mean a thing. What about me? All the rest of my family's in Slytherin – I told you that first day on the train.'

James chose to ignore this. 'What does he think he's doing, though, sitting next to Snivellus Snape?'

'Honestly, James, who cares?' Sirius said impatiently. Then he changed the subject and Harry turned his attention back to his breakfast with difficulty, his mind still dwelling on what he had overheard.