'Dumbledore wants to stop you having those dreams about Voldemort,' said Hermione at once. 'Well, you won't be sorry not to have them any more, will you?'

'Extra lessons with Snape?' said Ron, sounding aghast. 'I'd rather have the nightmares!'

They were to return to Hogwarts on the Knight Bus the following day, escorted once again by Tonks and Lupin, both of whom were eating breakfast in the kitchen when Harry, Ron and Hermione came down next morning. The adults seemed to have been mid-way through a whispered conversation as Harry opened the door; all of them looked round hastily and fell silent.

After a hurried breakfast, they all pulled on jackets and scarves against the chilly grey January morning. Harry had an unpleasant constricted sensation in his chest; he did not want to say goodbye to Sirius. He had a bad feeling about this parting; he didn't know when they would next see each other and he felt it was incumbent upon him to say something to Sirius to stop him doing anything stupid — Harry was worried that Snape's accusation of cowardice had stung Sirius so badly he might even now be planning some foolhardy trip beyond Grimmauld Place. Before he could think of what to say, however, Sirius had beckoned him to his side.

'I want you to take this,' he said quietly, thrusting a badly wrapped package roughly the size of a paperback book into Harry's hands.

'What is it?' Harry asked.

'A way of letting me know if Snape's giving you a hard time. No, don't open it in here!' said Sirius, with a wary look at Mrs Weasley, who was trying to persuade the twins to wear hand-knitted mittens. 'I doubt Molly would approve — but I want you to use it if you need me, all right?'

'OK,' said Harry, stowing the package away in the inside pocket of his jacket, but he knew he would never use whatever it was. It would not be he, Harry, who lured Sirius from his place of safety, no matter how foully Snape treated him in their forthcoming Occlumency classes.

'Let's go, then,' said Sirius, clapping Harry on the shoulder and smiling grimly, and before Harry could say anything else, they were heading upstairs, stopping before the heavily chained and bolted front door, surrounded by Weasleys.

'Goodbye, Harry, take care,' said Mrs Weasley, hugging him.

'See you, Harry, and keep an eye out for snakes for me!' said Mr Weasley genially, shaking his hand.

'Right — yeah,' said Harry distractedly; it was his last chance to tell Sirius to be careful; he turned, looked into his godfather's face and opened his mouth to speak, but before he could do so Sirius was giving him a brief, one-armed hug, and saying gruffly, 'Look after yourself, Harry.' Next moment, Harry found himself being shunted out into the icy winter air, with Tonks (today heavily disguised as a tall, tweedy woman with iron-grey hair) chivvying him down the steps.

The door of number twelve slammed shut behind them. They followed Lupin down the front steps. As he reached the pavement, Harry looked round. Number twelve was shrinking rapidly as those on either side of it stretched sideways, squeezing it out of sight. One blink later, it had gone.

'Come on, the quicker we get on the bus the better,' said Tonks, and Harry thought there was nervousness in the glance she threw around the square. Lupin flung out his right arm.

BANG.

A violently purple, triple-decker bus had appeared out of thin air in front of them, narrowly avoiding the nearest lamppost, which jumped backwards out of its way.

A thin, pimply, jug-eared youth in a purple uniform leapt down on to the pavement and said, 'Welcome to the — '

'Yes, yes, we know, thank you,' said Tonks swiftly. 'On, on, get on — '

And she shoved Harry forwards towards the steps, past the conductor, who goggled at Harry as he passed.

' 'Ere — it's 'Arry — !'

'If you shout his name I will curse you into oblivion,' muttered Tonks menacingly, now shunting Ginny and Hermione forwards.

'I've always wanted to go on this thing,' said Ron happily, joining Harry on board and looking around.

It had been evening the last time Harry had travelled by Knight Bus and its three decks had been full of brass bedsteads. Now, in the early morning, it was crammed with an assortment of mismatched chairs grouped haphazardly around windows. Some of these appeared to have fallen over when the bus stopped abruptly in Grimmauld Place; a few witches and wizards were still getting to their feet, grumbling, and somebody's shopping bag had slid the length of the bus: an unpleasant mixture of frogspawn, cockroaches and custard creams was scattered all over the floor.

'Looks like we'll have to split up,' said Tonks briskly, looking a.round for empty chairs. 'Fred, George and Ginny, if you just take those seats at the back . . . Remus can stay with you.'

She, Harry, Ron and Hermione proceeded up to the very top deck, where there were two unoccupied chairs at the very front of the bus and two at the back. Stan Shunpike, the conductor, followed Harry and Ron eagerly to the back. Heads turned as Harry passed and, when he sat down, he saw all the faces flick back to the front again.

As Harry and Ron handed Stan eleven Sickles each, the bus set off again, swaying ominously. It rumbled around Grimmauld Place, weaving on and off the pavement, then, with another tremendous BANG, they were all flung backwards; Ron's chair toppled right over and Pigwidgeon, who had been on his lap, burst out of his cage and flew twittering wildly up to the front of the bus where he fluttered down on to Hermione's shoulder instead. Harry, who had narrowly avoided falling by seizing a candle bracket, looked out of the window: they were now speeding down what appeared to be a motorway.

'Just outside Birmingham,' said Stan happily, answering Harry's unasked question as Ron struggled up from the floor. 'You keepin' well, then, 'Arry? I seen your name in the paper loads over the summer, but it weren't never nuffink very nice. I said to Ern, I said, 'e didn't seem like a nutter when we met 'im, just goes to show, dunnit?'

He handed over their tickets and continued to gaze, enthralled, at Harry. Apparently, Stan did not care how nutty somebody was, if they were famous enough to be in the paper. The Knight Bus swayed alarmingly, overtaking a line of cars on the inside. Looking towards the front of the bus, Harry saw Hermione cover her eyes with her hands, Pigwidgeon swaying happily on her shoulder.

BANG.

Chairs slid backwards again as the Knight Bus jumped from the Birmingham motorway to a quiet country lane full of hairpin bends. Hedgerows on either side of the road were leaping out of their way as they mounted the verges. From here they moved to a main street in the middle of a busy town, then to a viaduct surrounded by tall hills, then to a windswept road between high-rise flats, each time with a loud BANG.

'I've changed my mind,' muttered Ron, picking himself up from the floor for the sixth time, 'I never want to ride on this thing again.'

'Listen, it's 'Ogwarts stop after this,' said Stan brightly, swaying towards them. 'That bossy woman up front 'oo got on with you, she's given us a little tip to move you up the queue. We're just gonna let Madam Marsh off first, though — there was a retching sound from downstairs, followed by a horrible spattering noise — she's not feeling 'er best.'

A few minutes later, the Knight Bus screeched to a halt outside a small pub, which squeezed itself out of the way to avoid a collision. They could hear Stan ushering the unfortunate Madam Marsh out of the bus and the relieved murmurings of her fellow passengers on the second deck. The bus moved on again, gathering speed, until —

BANG.

They were rolling through a snowy Hogsmeade. Harry caught a glimpse of the Hog's Head down its side street, the severed boar's head sign creaking in the wintry wind. Flecks of snow hit the large window at the front of the bus. At last they rolled to a halt outside the gates to Hogwarts.

Lupin and Tonks helped them off the bus with their luggage, then got off to say goodbye. Harry glanced up at the three decks of the Knight Bus and saw all the passengers staring down at them, noses flat against the windows.

'You'll be safe once you're in the grounds,' said Tonks, casting a careful eye around at the deserted road. 'Have a good term, OK?'

'Look after yourselves,' said Lupin, shaking hands all round and reaching Harry last. 'And listen . . .' he lowered his voice while the rest of them exchanged last-minute goodbyes with Tonks, 'Harry, I know you don't like Snape, but he is a superb Occlumens and we all — Sirius included — want you to learn to protect yourself, so work hard, all right?'

'Yeah, all right,' said Harry heavily, looking up into Lupin's prematurely lined face. 'See you, then.'

The six of them struggled up the slippery drive towards the castle, dragging their trunks. Hermione was already talking about knitting a few elf hats before bedtime. Harry glanced back when they reached the oaken front doors; the Knight Bus had already gone and he half-wished, given what was coming the following evening, that he was still on board.

*

Harry spent most of the next day dreading the evening. His morning double-Potions lesson did nothing to dispel his trepidation, as Snape was as unpleasant as ever. His mood was further lowered by the DA members constantly approaching him in the corridors between classes, asking hopefully if there would be a meeting that night.

'I'll let you know in the usual way when the next one is,' Harry said over and over again, 'but I can't do it tonight, I've got to go to — er — remedial Potions.'

'You take remedial Potions?' asked Zacharias Smith superciliously, having cornered Harry in the Entrance Hall after lunch. 'Good Lord, you must be terrible. Snape doesn't usually give extra lessons, does he?'

As Smith strode away in an annoyingly buoyant fashion, Ron glared after him.

'Shall I jinx him? I can still get him from here,' he said, raising his wand and taking aim between Smith's shoulder blades.

'Forget it,' said Harry dismally. 'It's what everyone's going to think, isn't it? That I'm really stup — '

'Hi, Harry,' said a voice behind him. He turned round and found Cho standing there.

'Oh,' said Harry as his stomach leapt uncomfortably. 'Hi.'

'We'll be in the library, Harry,' said Hermione firmly as she seized Ron above the elbow and dragged him off towards the marble staircase.

'Had a good Christmas?' asked Cho.

'Yeah, not bad,' said Harry.

'Mine was pretty quiet,' said Cho. For some reason, she was looking rather embarrassed. 'Erm . . . there's another Hogsmeade trip next month, did you see the notice?'

'What? Oh, no, I haven't checked the noticeboard since I got back.'