A/N: This is my first ever story with more than one chapter. It's also on HPFF, so some may recognise it. Enjoy!

***

The TARDIS whined and groaned, throwing the Doctor on the floor.

'Ouch!'

He pulled himself up using the control panel, and whacked a couple of things with a hammer. The electrics were going haywire, and nothing was working properly.

'We must be in a place where there is a strong pulse of energy, which makes electricity go completely loopy…' the Doctor stopped talking, and looked around at the empty TARDIS.

'Oh.' He no longer had a companion. Before the sense of loneliness overtook him, the Doctor distracted himself by banging a few more dodgy buttons. Then the TARDIS suddenly lurched, and stopped.

'What?' The TARDIS was completely still. Picking himself up, the Doctor loped over to the door, and peeked outside. He was expecting to be in some kind of war zone, with high levels of energy, which could have interfered with the TARDIS's circuits. What he didn't expect to see was a corridor that belonged in an old, medieval castle, most probably in Scotland.

Slipping out the doors, the Doctor strolled down the empty corridor, his hands in the pockets of his coat. He pricked his ears up slightly, and heard voices reverberating down the empty place. He drew closer to the wall, in a half-hearted attempt to hide.

'Really, Ronald, I don't know why you don't do your homework when you have time, rather then leaving it to the last minute.' An annoyed voice, belonging to a girl, echoed down the corridor.

'I was busy 'Mione, Harry was holding a lot of Quidditch practices, and I really needed to practice…' protested 'Ronald'.

'McGonagall's going to absolutely murder you, it was late to start with, and she gave you another weekend, because you told her you got caught up with prefect duties…'

'You really are in for it, mate,' said another boy's voice.

The Doctor decided they were no threat and stepped out from the shadows into the middle of the corridor. The three teenagers, about 16-17 years old, were very surprised. The girl dropped the books she was holding, and shrieked, the boy with ginger hair jumped backwards and the black-haired boy drew a long, thin stick of wood and pointed it threateningly at the Doctor.

'Whoa, hold your horses.' He held up his hands to show he was unarmed. Now all three had their sticks trained on him.

'Who the bloody hell are you?' asked the ginger boy.

'Ronald!' hissed the girl.

'Well, Ronald,' grinned the Doctor, 'I've got some questions too. Why is there, for example, a strong energy pulse around here, which is stopping my magnificent, and very high-tech, spaceship from working?' They gaped at him.

'Spaceship!' squeaked the girl.

'Yup.'

'Ecletricity doesn't work here,' said Ronald.

'And where might 'here' be?' asked the Doctor.

'Hogwarts School of Witchcraft and Wizardry,' said the black-haired boy, who had so far remained quiet, and the Doctor had a distinct feeling he was being analysed.

'No! Never, this can't be Hogwarts!' said the Doctor, incredulously.

'Well, it is,' snapped the girl. The Doctor suddenly knew who they were, and he glanced at the black-haired boy, catching sight of a lightening scar before the boy shifted uncomfortably and his hair covered it.

'My name's the Doctor,' he said, holding out his hand for them to shake. The girl took it.

'I'm Hermione Granger, and this is Ron Weasley and Harry Potter,' she said, shaking his hand.

'Why are you here?' asked Ron.

'I didn't mean to end up here. I must have got too near, and the pulse made the circuits stop working, so the TARDIS just cut out. The TARDIS is my ship, by the way,' said the Doctor, seeing the bemused faces. He patted the blue box. They all started, as though the TARDIS had just appeared out of thin air. Which to them, it had, thanks to the perception filter. The Doctor grimaced. The filter would most probably leak to the surrounding area, so anyone standing in that particular part of the corridor may suddenly find themselves ignored for a while after the TARDIS left. If it ever did leave…

'We'll take you to Professor Dumbledore, he'll know what to do,' said Ron.

'No, he's not here. I tried to see him yesterday, but McGonagall told me he's gone and isn't coming back until Sunday,' said Harry.

'We could go and see Professor McGonagall, I suppose,' said Hermione thoughtfully. Then Ron's stomach rumbled.

'Maybe we should go to breakfast first,' he said.

'Good idea, we'll be able to think better after food,' said the Doctor. Ron nodded approvingly while Hermione rolled her eyes at him.

'And we've got Transfiguration first thing, so we can talk to her then, and with this distracting her, she might forget about my late essay,' he said.

'Yeah, right Ron,' snorted Harry, 'she'll never forget that in a thousand blue moons.'

'It's worth a try,' Ron said, his smile only slightly wavering.

They walked down to the Great Hall. The Doctor hesitated at the doors.

'I don't think I should just walk in, I might cause a bit of a stir.'

'Kitchens it is, then,' said Harry, and they turned back, bumping into a small, flustered red-head.

'Oh, hi Ginny,' said Hermione. Ron grunted and Harry went slightly red.

'Hello, I'm the Doctor,' he grinned. She looked up at him, confused.

'Wha…'

'Never mind Ginny, just move, we have to go before people see…' said Ron, looking around shiftily. Ginny looked murderous.

'Why are you always trying to leave me out, Ron? I'm not a baby; I'm only one year younger than you! Why shouldn't I be told what's going on, and why there's a strange man in Hogwarts?'

'Well said,' said the Doctor, and then, 'Do I really look strange?' They ignored him.

'We don't know who he is, but he's stuck here, and Ron's hungry, so we're going to the kitchens,' said Harry.

'Ok…' she said slowly. 'I'll come with you then, I don't really want to face Dean at the moment.'

'Who's Dean?' asked the Doctor. He was ignored again.

'Really? Why?' asked Harry, trying to look casual.

'I'm a bit pissed off at him at the moment, and no, Ronald, I'm not going to tell you why,' she rounded on Ron, who had begun to open his mouth.

'Are you two related?' asked the Doctor.

'Unfortunately, yes,' spat Ginny.

'Anyway…' said Hermione, 'Aren't we supposed to be going to the Kitchens?'

'Oh, yeah.' They made their way across the Entrance Hall, the Doctor trying to look inconspicuous, and failing miserably.

'We should really get you some robes, if you're going to be stuck here for a while,' sighed Hermione. 'You can't go around in that get-up.'

'I rather like my coat, thanks.'

'Yes, it's lovely, but this is a wizard school, and most people wear cloaks and robes. You look like a muggle.'

'Are you? A muggle, I mean,' Ginny asked.

'Well, I…'

'If you were a wizard, wouldn't you have been sent a letter when you were eleven?' asked Ron.

'When I was eleven, which was a very long time ago…'

'It can't have been that long ag…'

'I wasn't on this planet. I'm from Gallifrey, home of the Time Lords, and I'm 900 years old.'