Harry spent quite a lot of Saturday doing school work.

That didn't just mean homework, although there was a long shared session of doing homework for Harry and his friends in the Gryffindor common room while rain lashed the windows. They went through every subject any of them was doing except for Arithmancy, and that exception was only because Seventh Years had Arithmancy on Monday so there hadn't been a chance for Hermione and Neville to have an Arithmancy lesson yet. Let alone have any homework to do for it.

Harry spent the rest of the time – the time while Neville was doing Herbology, and Hermione was doing Potions, and Dean doing Divination and Care of Magical Creatures, and Ron doing Astronomy – working on the three separate ideas he'd had for Runes projects, plus writing out other things he wanted to look into or do at some point over the course of the year. It seemed like it was a good idea to keep the notes, and add to them when an idea came along, rather than forget and have to have the same inspiration three or four times.

Seventh Year was a year of school, which was one thing, but it was also a year when Harry had access to the Hogwarts Library. Including the Restricted Section, which was a remarkable collection of books that might not be equalled anywhere else in the country – Albus had told Harry in the past that he'd actually removed books about Horcruxes from the shelves, which gave some sort of indication about just how comprehensive the collection had to be.

It was just a bit of a pity that – as Madam Pince had explained to him in terse tones – about ten percent of them were enchanted in various worrisome or vexatious ways. The ones which screamed unless silenced beforehand were quite common, but there were some which slammed closed unexpectedly on the reader's fingers, some where the page you were looking for went missing unless you went one page at a time, and apparently a rumour of one which wrote itself in the blood of the person reading it.

(Harry didn't think that one was true, though. The rumours about it never said what book it was, and really if you were reading a book and it turned out to be written in your own blood he thought it was only sensible for the person who'd had that happen to remember which book it had been.)

In any case, though, Harry found himself with a clear slate by Saturday evening, and so on Sunday he decided to go to town for new books.

Not Fort William, though. Much as he'd come to like the Highlands town, there were other places with a lot more variety of the sort he was picturing.

That Sunday, around ten in the morning, Harry climbed over Hogwarts into the a sky of blustery wind and scattered cloud.

The rain from yesterday and last night had left the soil and the trees dripping wet, and that hadn't quite worn off, but it wasn't raining now – at least, not around Hogwarts – and Harry climbed to what he thought was about five or six thousand feet before levelling off and flying south.

This was all something he'd sat down and worked out with an atlas back in August, not wanting to overstrain himself, and Harry kept flying for perhaps ten minutes before deciding he had to be outside the Hogwarts Anti-Disapparition Jinx.

Then he focused on his Destination, brought up his Determination, and paused for just a moment to be sure before acting with Deliberation – and vanished with a crack.

It was quite a long way to London, and while going quite a long way was the sort of thing you could do when Apparating – it was, after all, the whole point – Harry had decided to go in shorter jumps instead, and more of them. It didn't add much to the time the journey would take, and it was good practice, so his first Apparition jump took him from south of Hogwarts to a point about a hundred miles away… specifically, the air a mile or so over the Scottish city of Glasgow.

Something about it made it look different to London from the same height, but Harry couldn't quite put his claw on it. It was big enough that it was a large blob of city from this altitude, rather than being like many towns where Harry could see the edge, and it even had a river running through it, but… there was something about it and Harry wasn't quite sure what.

Maybe it was something to do with the houses? Though it could also be the golf course visible off to the south, which wasn't the sort of thing you saw in London.

Shrugging his wings, Harry orbited for a minute or so and then focused on his next Destination.

This time, he appeared over Lake Windemere, one of the lakes which the Swallows and Amazons books were based off.

Harry could certainly see the appeal of the lakes, though as someone who'd spent the overwhelming majority of his last six years in Scotland and many of his weekends flying through the Highlands on the way to Fort William he had to conclude that the mountains – while nice, and picturesque – weren't really as impressive as proper Scottish peaks.

Like Glasgow, Harry had never been before, but there was only one Lake Windemere – like there was only one Glasgow – and both were suitable Apparition destinations for that very reason. It would help now that he'd actually been there, and Harry turned his mind to his next destination before Apparating for the third time in as many minutes.

Sheffield – Harry's third waypoint – looked more different from both Glasgow and London than either had from each other, at first impression, though that was mostly because Harry had appeared directly over a very large building surrounded by car parks.

It looked like a shopping centre to Harry, or at least that was his first guess, and he stayed for an extra few minutes over Sheffield compared to the first two. Partly that was so he had a better idea of how the place looked (though the shopping centre was still quite a good Apparition point) and partly because he wanted to get a sense of the rivers – unlike with both Glasgow and London, and for that matter even Fort William, the river in Sheffield just wasn't very big.

It looked more like a canal than anything.

Still, that was hardly something to look down on the city over except in the most literal sense of being overhead, and after his curiosity was satisfied Harry Apparated for the fourth time.

Milton Keynes was different again.

It was a New Town, Harry knew that much, but the difference from the air was still quite impressive.

There was a lot more green on the ground than there had been in the other cities (if Milton Keynes counted as a city rather than merely a very large town), and it was also blindingly obvious from up here that Milton Keynes had – as had indeed been the case – been designed all in one go. It was also more spread out than the other cities, and that meant that the main roads with their belts of trees delineated the individual neighbourhoods so effectively that Harry could see them without even trying.

It was sort of as if someone had taken that bit of a city which you could only get in a city, the shopping centres and big cinema and things like that, and put it in the middle of a countryside before drawing out a grid and putting a village in each grid square big enough to just about fill the square… which, now Harry thought about it, was pretty much exactly what had happened. They hadn't even finished building some of it, either, with at least one of the areas where a City Centre Bit should go still consisting of a green field with a car park.

Harry wondered what the people of the original Milton Keynes had thought, when an entire city had more or less landed on top of them.

Then he focused on the familiar image of the Barbican in London, and Apparated south one final time.

It took a bit of time in the library for Harry to really be sure of the kinds of books he wanted, and he then went out and got copies of them from likely-looking bookshops.

Some of the ones he got were books that were meant to teach children to read, while others were ones which were intended to teach adults who knew a language that wasn't English. Harry wasn't sure which of the two would be more appropriate here, but it felt like getting some of both would be good.

Then the third type of book Harry got was some of the good but simple stories he remembered from primary school – sometimes the same type, and other times something different but which was the same sort of thing. It felt like it would be a good idea to have some of those, so that Empress could enjoy her progress.

One thing he did wonder about was that often you could sound out new words to get what they meant if you'd already heard it, but you couldn't do the same thing when you were reading a language you didn't speak. But then again Dragonish worked in really strange ways because it was a magical language, and maybe it'd be a useful way to do things.

It was the sort of thing where Harry thought maybe he should be taking notes or something, because while Empress could teach dragons to speak she couldn't teach them to read. Though admittedly giving Nora her first lessons in how to read had been considerably easier because Harry and Hagrid could look at the same book as her and have her point to things or scratch letters on the ground.

It just hadn't occurred to Harry to take notes about that bit, and he couldn't remember how it had gone.

Harry's trip back north took a bit less time, only a couple of minutes, and it actually took him longer to go from his Apparition point to reach Hogwarts itself.

It left him with a pleased feeling of having accomplished his goals, though that just reminded him of something else he'd been planning to do – writing out the description of the Unusually Shaped meetings, scheduling a classroom and weekday to have it on, and then posting it up on the noticeboard in good time.

He could have opted for just about any afternoon, but after some consideration Harry opted for Saturday evening. There weren't any major clubs up on the noticeboard yet which overlapped with it, and it was a day where Harry could be pretty sure he wouldn't be keeping someone from urgent homework or from their sleep before an Astronomy lesson. (If for no other reason than that they could have any needed sleep at a different time on Saturday, or sleep in on Sunday – or, knowing many teenagers, both).

"Is that something we have to attend?" Hans asked, as Harry followed up a Sticking Charm by using a drawing pin just for redundancy. "If we're not all human, I mean."

"You don't have to, no," Harry told him. "And legally speaking, June for one is actually not only human but technically pure-blood."

Hans gave him a deeply confused look. "What?"

"June's descended from a werewolf," he explained. "It's sort of complicated, but for at least two generations back all her ancestors are werewolf-descended wargs. They're magical, so she's pure-blood, and because they're descended from a human then they count as human as well."

"...that's weird," Hans summarized. "Not her, the law, I mean."

"I think most laws are like that," Harry said. "Or, rather, I assume most laws are like that."

Hans chuckled. "Nothing I have to deal with yet."

"Take it from me, you'd be surprised," Xenia advised, trotting up. "Can I ask you something, Potter? In private, if that's okay."

"So…" the centaur girl said – Harry wasn't sure if the right term was filly, it was a bit of a weird question to ask. "I know my cousin has some horse shoes, but I don't know where he got them. Or why."

She folded her arms. "He's very defensive about it."

"We went to Hagrid about it," Harry said. "And… it's because normally horseshoes are only needed for an animal with a hoof if it's walking a lot on hard surfaces. So because horses do a lot of that kind of walking, and have done for centuries, while centaur mostly live in the woods and don't… and because Muggles don't know about them… all our words about it and our thinking about it is related to horses doing work."

He paused. "Maybe thinking of them as hoof shoes would be better?"

"That does sound like it wouldn't annoy my parents," Xenia conceded. "But horseshoes is simple enough for me."

"Hagrid, then," Harry decided. "He's probably sorted more than one set out for Conal by now."

The first Board Games club meeting came around before the first meeting of the Unusually Shaped society, and Harry had a feeling that something interesting was going to happen there.

Admittedly, this was partly because Anna had owled him telling him something interesting was going to happen, but that kind of deduction was the sort of thing which you had to have as a Head Boy. (Or it was at least as far as Harry was concerned, if only because the sort of person who didn't think something interesting was going to happen based on that sort of clue was probably roughly as intelligent as a doorstop and quite possibly even less useful.)

The tricky bit was to see if this was some kind of way to get him somewhere specific, either for a prank to happen there or so that he wasn't somewhere else where they could do something. Accordingly, Harry decided that the simplest approach would just be to ask Hermione to keep an eye on things – specifically on the Smiths, though not to the exclusion of anyone else – and go and see what they wanted to show off.

It turned out that he wasn't the only one there, by any means, and there were more than forty students forming a couple of ragged rings around a table. The younger and therefore shorter boys and girls were in the front, with anyone particularly tall in the rear ranks, and Harry put his forelegs on a chair so he could rear up and crane his neck over the crowd.

Both Smiths were there, which was a bit of a relief, and they had something which looked like a double-sized chess board (or, rather, a chess board with double the normal number of squares in each direction, so really a four-times-the-size chess board) on which they were setting up ranks upon ranks of chess pieces.

There were four kings in the back rank, and four queens in front of them, and a row of rooks on the flanks. They had a whole legion of pawns, enough to fill five rows, and more rooks intermixed with knights and bishops behind them.

It took the two kitsune a couple of minutes to finish, so that there was a six-row wide gap between the two large chess armies.

"We call this Accurate Chess," Tyler explained. "First, you set it up, like this."

"Then," his twin went on, picking up, "you give them all the instructions about what you want them to do. In this case, we told them what to do before the game, but that's a lot of the skill."

"Yep," Tyler agreed. "And you need to be careful you don't give the other player clues about what you're planning, because if they know they could make their own plans to deal with yours."

Someone made an ah sound of realization.

"It's like a real army, then," she said. "You have to send out orders ahead of time."

"Exactly!" Tyler confirmed. "And then, when you're both ready to begin…"

He touched his wand to the big board, and a few seconds later Anne did the same.

What happened next defied easy description.

There were more than a hundred chess pieces on the board, and as soon as both Smiths had their wands on the table every single one of them charged with a tinny roar. The pawns rushed at one another and started trying to beat their opponents down with headbutts or kicks or punches, bishops stomped in behind them laying about with their croziers, and knights charged before colliding with a crash that left fragments all over the field.

Harry could see absolutely no rhyme or reason in what was going on, every single piece just trying to beat up any of the other side that they could see, and when the carnage ended just thirty seconds later there wasn't a single intact piece on the board.

"…was there a point to that?" Dennis Creevey asked eventually.

"Well, it was funny," Tyler said. "I won't lie, we're still working on it."

"Our main focus this term will be on the malleability of Charms," Professor Flitwick told them, brightly. "It's a topic which we've already covered, to some extent, but we'll be seeing it more and more over the course of the next few months."

He swished his wand through the air, and a book flew off the shelves before opening to a particular page and expanding to the size of the blackboard. "By this stage in your magical education, it's considered reasonable that you'll be able to cast almost any charm in the Standard Book of Spells with a little self-study, so if there's something you need to do which isn't in the normal set of Charms you've already learned you have four ways to do it."

Flitwick's wand highlighted the four headings in the book. "Firstly, there is by learning a normal new charm which you just don't happen to have run into yet, as I was just describing. This is situations such as needing to erect a tent, something many of you will not yet have had the need to do, or perhaps mix the perfect cup of tea."

Neville put up his hand. "Does the milk go in first?"

"I'm quite sure you'll find that out yourself, Mr. Longbottom," Flitwick assured him. "The second way is by learning a very difficult new charm, the sort which you have heard described as NEWT-level. We will be covering those in the summer term, after Easter, because they are often on your NEWTs – one example being the Patronus Charm, though I know many of you have already learned it."

Harry felt quite pleased by that.

"The third way is by creating a new spell for the purpose," their Professor said, and here he became slightly solemn. "Though designing new Charms is often dangerous, because the magic does not always do what we would like it to and it can produce unexpected and unwanted results… but we will be covering that next term, and how to do it safely."

He finally brought his wand to the topic he'd started the lesson with. "And, finally, the fourth method is by using a Charm with a similar effect and applying malleability. This is that rather than casting the spell precisely, you cast it with a little wiggle room and can shape it in the way you would like. Can anyone think of an example?"

Several hands went up, and Professor Flitwick called on Ron first.

"It's like the sort of effects you get when you cast a spell wrongly, but doing it deliberately," Ron said. "So normally bluebell flames are only warm to the touch, and don't burn you – but you could cast it with malleability and get them hot, hot enough to make tea – or, say, cool and only giving off light, and use them that way."

"An excellent point, Mr. Weasley!" Flitwick agreed with a smile. "It is like the effects you get when you cast a spell wrongly, indeed. I'm sure people can think of others?"

"...so I've got a question for you," Hans said, apropos of nothing much.

"For who?" Luna checked.

She leaned back on her chair, which was a particularly nice one. Harry had decided that he may as well get some Transfiguration practice in, and turned all the chairs in the classroom they were using for the club into different sorts of chairs or ways to sit down – not all of them had actually ended up being used, admittedly, but the beanbags had been a big hit among the quadrupeds.

"There's plenty of us here," she went on. "In fact, I'd say you could be talking to anyone who's here, since anyone who's here can hear."

"Hear hear," Tanisis said.

Hans stifled what was either a chortle or a giggle.

"It's for, well, June, and Conal, and Matthew, and Xenia as well I suppose," he told them. "I was wondering what it's like in the Forbidden Forest these days – and if it's likely that there's going to be an Acromantula student at some point."

"There might be one of those," Harry said, thinking about it. "I'm not really sure how much politics goes into who gets Hogwarts letters, but I know there must be some."

"Politics between who?" Isaac asked.

Harry was about to explain, but Tiobald held up a hand to signal that he wanted to talk.

"I think," he began, in a slightly tooth-grating accent, then glanced at Luna and signed something quick.

"I'd say keep going until you run into a sound you have trouble with," Luna advised.

The merman (or merboy – was the difference when you turned seventeen?) nodded, and took a deep breath. "I think you don't need two p-p-"

He looked annoyed, then his hands flicked through some more signs.

"You don't need two people for politics," Harry said. "I'm guessing you're having trouble with the P sound?"

"More than that one," Tiobald agreed, nodding.

"You're doing well," June told him. "Take it from me. Unless you've been practicing for longer than I think, anyway."

The selkie shot Luna a begging look, and Luna smiled back. "It was something we realized over the summer," she explained. "OWLs are this year for him, and unless he wants to spend the whole of some parts of the practical exam asking the examiner to stick his head in a bathtub, it might help to be able to speak English."

"My accent is a-," Tiobald sad, then looked distinctly annoyed that he'd managed to run into another P sound.

"Pain?" Mopsy guessed, and got a grateful nod.

"Well… to tell the truth, I think there's a lot of politics going on back with the centaur herd," Conal said. "It's… you know what it's like when adults are arguing about something where they don't want you to know about it? But you know they're arguing anyway because of the way they talk, and the way they talk much more quietly when they know where you are?"

Harry hadn't had much experience of that because his aunt and uncle had never really been quiet about that sort of thing – though they hadn't had many arguments, really, all things considered – but he thought he got the idea, so he gave a vague sort of nod. There were several much more emphatic nods from most of the rest of the room, including Hans who'd originally asked the question.

"What I think is that… okay, so there's some centaurs who think that wizards are awful and they're never going to be convinced otherwise," Conal went on. "But there's some who like wizards a lot, like Firenze, and there's some who aren't sure. And normally it's kind of hard to tell who's who, except for the ones who think wizards are awful because they mention it and everyone goes quiet."

Xenia coughed. "Which is usually about the time we're told to go to bed."

"Yeah," Conal agreed. "Pretty much. But… Father told Bane to shut up, last time it came up. And then I got told to go to bed."

They considered that.

"That sounds like an improvement, to me," Isaac said, a bit cautiously. "Is it?"

"I think so," Conal agreed. "But it does feel a bit like deciphering a puzzle. I could be wrong."

"Humans have that kind of thing too," Harry supplied.

"Are you allowed to talk about that sort of thing?" Anne checked.

Harry shrugged. "I grew up among humans… would it help if I said conventional wizarding culture?"

"Probably for the best," Cottontail told him. "Because there's some non-humans in it, or part-humans."

"I think I can comment on it," June said. "So can Matt."

The younger warg snorted, then tilted his head a little.

"Actually, is there anyone in our lot who doesn't like what we're doing?"

"I think Aunt Elm might count," June said, after thinking about it. "You know what she's like."

"I don't," Melody supplied, sounding interested. "What is she like?"

Matthew snorted, tongue lolling out in a canine laugh. "You explain it, June, you're the one who brought it up."

"I think I'll leave it to you," June decided. "I'm a Prefect and have to work for better relations at school. You're an underclasswolf who's not supposed to be insightful enough to avoid making those mistakes."

"...wait, is that how it works?" Matthew asked, glancing at Harry. "That doesn't sound right, somehow."

"Well, I'll be mogadored," Flopsy groaned. "We should have been doing that earlier! Now it's too late, we're too old for it."

"We could still try," Cottontail said.

"Nah, Mopsy would rat us out," Flopsy said.

Dominic rolled over onto his front, raising a paw. "What's a mogadore and how are you it?"

"Never you mind," Mopsy told him severely.

Harry had looked it up after it turned up in a Discworld book once, and he was fairly sure that to be mogadored was to be confused.

It was another question entirely whether the Barlos girls knew that, though. And it did sound like quite an impressive swearword.

The main other thing that happened during that meeting – apart from the general getting-to-know-one-another, that was – was Flopsy, Mopsy and Cottontail asking Harry about advice for being a Prefect and also advice for not being a Prefect but always being around one.

Harry gave the first one some thought, and told Mopsy that the important things as far as he was concerned were to try to be fair and help people more than be absolutely sure that the rules were followed exactly. At the same time, he said that it was also kind of inevitable that some of the things she decided were going to make some people unhappy sometimes, and that rather than try to keep everyone happy all the time she should use her best judgement about the situations when someone was bound to be unhappy anyway.

Then for Flopsy and Cottontail, Harry suggested the much simpler solution of asking Sirius about it. Since Sirius had been close friends with Remus for their time at Hogwarts it seemed only reasonable to Harry that Sirius would have at least some insight into the question.

Admittedly, it wasn't perfect, but it might be useful.

Things started to settle into the comfortable and familiar routine of Hogwarts during the school year, as it became normal for Harry to expect Charms and Defence on a Monday followed by a free afternoon.

At the same time, though, there was a strange sort of feeling of passing something on. The Dungeons and Dragons campaign in that club was retired, because Harry wasn't sure he'd have the time to keep doing the extra work required to run it, but instead Colin volunteered to take over running it – at least for the year, if not for his Seventh Year as well – and promptly put together a very different sort of adventure where Harry had his first chance to just play a player instead.

What made Colin's game different was firstly that it was a much higher level game – everyone started off powerful, rather than growing to become powerful from comparatively humble beginnings – and secondly that rather than being in the world of Lord of the Rings as its basis it was in a more sort of modern-world setting – comparatively speaking, anyway, there were steam ships and stuff – and one which within twenty minutes Harry was fairly sure had taken some inspiration from the Discworld, even if it definitely wasn't the same.

There were trains, but they weren't like the Hogwarts Express with steam engines – instead they were towed by giant magically animated horses. And there were dungeons, and adventures, but you had to not just do the job but prove you'd done the job, often with photographs – and in some cases there were people who faked doing the job you'd taken first.

Plus, when someone made a mistake with their character, instead of handling it the way Harry would have done (which was to just go back and let things happen properly) Colin had their enemies stop and cough awkwardly while everyone got back into their places and they did it again. Sort of like it was a play.

It was a bit silly, and Harry didn't always agree with Colin's choices, but it was fun enough to play his character (which Harry had made as a cleric, but one who healed people by telling them they were fine really and it just working – which, as it turned out, fit with the flavour of the game quite well) without having to do all the organization work involved in making the whole of the world for them to play in.

As the Quidditch Captain, Ron was involved in the team in Seventh Year just as he'd been involved in previous years, and they needed one new Chaser to replace the now-graduated Cormac. That meant being involved in a bit of a controversy over who was to be that new Chaser, because a First-Year Gryffindor had demonstrated excellent broom-handling skills despite being Muggleborn and that led to a lot of argument over whether First-Years were actually allowed on the Quidditch teams.

Draco diffidently pointed out that it wasn't like anyone else had had the chance to pick from the First-Years in any of the previous years, and Ron replied with what Harry thought was the very good point that the rules didn't actually forbid it. Then Zacharias had said, sounding almost against his will, that really in most years it wasn't like people wanted to pick a Firstie who usually hadn't qualified on a broom as one of their Quidditch lineup.

That led in turn to the last of the Quidditch captains weighing in, Ravenclaw's Jasper Bradey, and he said that it was in the rules that First-Years couldn't own their own brooms.

"So… it sounds like she wouldn't be allowed her own broom," Harry said, thinking. "But it'd be okay if she played, given that?"

"Startling as it sounds, Potter, most of us can't fly without a broom," Draco countered.

"Well, yes," Harry nodded. "But I know I did broom flying lessons here during my first year, and I didn't own a broom then. And it's only because Kayleigh has done a flying lesson and been really good that we're even talking about this at all, and she still doesn't own a broom."

"Mate, are you saying that the answer is just that she has to fly on someone else's broom?" Ron said.

"Well, I think that would work," Harry explained. "It would mean she's not breaking the rules, or at least not that one. But I'll check with the headmaster to make sure."

Ron frowned. "That means I can't just tell her she's got in, right?"

"Afraid not," Harry told him.

"And I can't just do normal trials, either, because I might disappoint someone?"

Harry shrugged. "Sorry."

He did feel a bit bad disappointing Ron like that, but he liked to think that he'd have done the same sort of thing with anyone else – which meant he wasn't being biased, probably.

It was hard to tell.

As September became October, and Kayleigh settled in on the Gryffindor Quidditch Team – she was reportedly a good fit for Chaser, possessing the skills necessary to steer with one hand and occasionally go hands-free for a catch, and had done netball in primary school so was good enough to be going on with at the throwing and passing as well – Harry's subjects all got very NEWT-y.

They were focusing on Cuneiform in Runes, which meant a whole different set of relations of one rune to the next – or, rather, five different sets because of the five types of script –and it was complicated by the fact that Cuneiform worked on words, not letters, but the words had been the genesis of syllabic sounds. So a working runic sequence would ideally be one which had the right individual meanings (for Harry's telescope, that would mean including the words for Star and Sky and Light and Power) but where if you read it out in Akkadian or Sumerian it would have a complementary meaning rather than one which was dissonant.

The alternative was to space the runes out so much they didn't actually interrelate with one another, but that was a lot cruder and a lot less effective – so much so that it normally wasn't worth bothering with.

"Okay, so… the idea is, you set up your complete sequence," Ron said, thinking out loud. "And then you split it in as few places as possible?"

"Exactly," Hermione agreed, with a nod, and pushed a sheet of paper over to him. "You want the sequence to form beneficial words, and you're okay with neutral words, but you don't want bad ones. So this one would be?"

Ron paged back through one of the dictionaries scattered around their table. "Um… hold on. So this is meant to be about making something stronger, right? As in, tougher, harder to alter?"

"Right," Harry agreed.

"But that one's… hold on, that's going to end up making…"

Ron's voice trailed off into mumbling for a bit, and he flicked back and forth a couple more times.

While he was going, Harry carefully drew out the sequence in question.

He thought he knew what it meant, but he'd just had an idea.

"That bit there," Ron pointed. "It's 'strong' and 'you', but that's going to end up meaning, um… violently, isn't it? So it's the wrong derivation from strong."

"Exactly," Hermione said, pleased, and Ron drew in a pair of vertical lines to indicate a word break where they'd have to separate the text.

Harry then put his wand against the sequence copy he'd written out. "Xenographia."

A new piece of paper appeared on top, this one in English.

"...well, now I feel a prat for not realizing that," Ron said. "Could we have done that any time?"

"It is a language," Hermione frowned. "But I'm not sure this is going to cover all the nuances."

"Of course not, it's a tool, that's all it is," Ron shrugged. "It just makes a bit of it a bit I'm not going to inscribe something that might blow up when I could use this to check."

The week before Halloween itself, Sirius sent Harry a letter on Saturday morning to let him know that there was something Sirius wanted to show him.

"Did you come from London or from Hogsmeade?" Harry asked Hedwig, and she barked in a self-satisfied sort of way which gave Harry no clue what the answer was.

When you thought about it, she could have been sent from London and just gone through the Floo for a quicker journey. Or been sent from Hogsmeade and gone through the Floo to stretch her wings.

Wondering if he'd ever know, Harry finished his breakfast and headed out the front door. Nora was busily trying to explain something to Horst not far away, about how you had to be careful where your tail went because it could be dangerous if it hit someone, and Harry listened in for a bit and gave her a wave before opening his wings and taking off into the crisp morning air.

There were some days it was easier to fly, and some days it was harder, and this was definitely one of the easier ones. Harry spent an extra minute or two luxuriating in it, delaying the flight to Hogsmeade (which was really quite close by, after all) before gliding down to land neatly just outside Dogwarts.

"Morning, Harry," someone waved – Cyril Meakin, who Harry knew as a Prefect from a few years ago and who he vaguely remembered now worked in the village. "Early start on the Hogsmeade visit?"

"Visiting my Dogfather," Harry replied, and the young man laughed.

"Glad I don't have to rush to man the counter just yet, then. You take care."

The unexpected interaction gave Harry a nice little lift, not that he needed it when visiting Sirius, and Sirius didn't seem to need it either – grinning broadly as he let Harry in.

"You're going to love this," he explained, ushering Harry down the stairs into the basement. "It was a bit expensive, but Remus's lot and I got it puzzled out between us."

The big room in the basement was the one which didn't really have a single purpose, and Sirius still hadn't given Harry a clue – not until he reached the bottom, and saw some obviously Muggle paraphernalia all hooked up together with a nest of wires.

"Is that on?" he asked, then shook his head – it was a silly question, he could see all the lights which indicated that it was. "How are you powering it?"

"That was my idea," Emily said, sounding very proud of it. "It's one of those uninterruptible power supply thingies, only it's been magicked so that it doesn't run out of power as quickly."

"I'm not sure why they call it uninterruptible if it can run out anyway," Martin shrugged.

"Anyway, the important bit isn't that it's on," Sirius said, sounding impatient. "Come on, Remus, let's show him the important bit."

"All right, all right, keep your fur on," Remus replied, with a laugh.

He picked up a remote control, inspected it, then put it down and picked up another one. "This one first, I think."

One of the things in the pile went clunk and started to whirr faintly, and a big square of wall on the other side of the room lit up in the sort of way things light up when the light that's lighting them up is the light meant to indicate being dark. Like a movie screen when it's showing black, or something like that.

Then one of the werewolves crowded into the corner of the room pressed a button on the other remote, and very suddenly Harry was watching Airplane!.

Quite early on, the bit with the smoking ticket.

"There's a pile of stuff that didn't work in one of the other rooms," Sirius told him. "What do you think?"

"I'm really impressed," Harry said, as Martin tried not to break down laughing at one of the jokes. "I think Hermione is going to want to see this…"

As Harry had predicted, Hermione did indeed want to see it.

She also made a list of the things which had worked and the things which hadn't. There was a normal television which hadn't worked, and a computer monitor which also hadn't worked, and the first projector they'd got hold of which hadn't worked either. On the other hand providing sound had proved fairly easy, it seemed, and that went down on the list as well.

"Right," Hermione said, eventually, looking at the results. "And… wasn't that story from Professor Dumbledore about why it was thought that electrical things don't work at Hogwarts?"

"It was about a world war two aircraft, I think," Harry answered, trying to remember. "And everything about it stopped working. The engines and the radar and things like that."

Sirius pondered that.

"Does it help that the videotape player works fine?" he asked.

Hermione tapped her paper, which already had the video machine written down. Then she frowned, pursing her lips slightly.

"So we know that a normal television works even in a magical environment, just not at Hogwarts," she said, thinking aloud. "And a flat screen works fine, and so does one projector but not the other."

"It seems like those projectors are the most important clue," Harry contributed. "They're almost the same, but not quite exactly the same."

Hermione nodded. "Exactly… can someone get the boxes?"

Sirius was the only one who knew where the pile and the boxes had gone – all the werewolves in the house had been sucked into watching Airplane! - and when he came back some minutes later Hermione put the two of them side by side.

"That one says it's an LCD projector," Harry said, pointing. "So does that mean the other one isn't?"

Sirius chuckled. "I'm not really sure what LCD means, but it sounded different, and it said it didn't need degaussing or stuff like that so I thought it was worth a try."

"That other one's a cathode ray tube," Hermione realized. "I think – hold on, I need to check something. Can you Apparate in Hogsmeade?"

Hermione came back about ten minutes later with a pair of big Muggle books, and thumped one down on the table.

"Steady on," Sirius blinked. "This is starting to look too much like homework."

"Does it count as homework if it's fun?" Hermione replied, looking up from the table of contents. "Because I could point out the same thing about a self-referential Protean Charm."

Harry watched as Sirius had an argument with himself, trying to find a way to say yes and no at the same time so he got away with it. Finally he sighed, shaking his head, and made a sort of tsk noise.

"You win," he conceded. "Where did you get those, anyway?"

"Bletchley Park," Hermione answered, already flipping to the page she was after. "It's a museum about World War Two codebreaking, they had some early computers there, and this involves… aha!"

Harry and Sirius crowded around.

"Valves?" Harry said, confused, but started reading. "Aren't those those things which you need to turn off when the plumbing goes wrong?"

"It's an old electrical term," Hermione clarified. "They got replaced by transistors, which are smaller, but those were only invented in the nineteen-fifties or sixties. And something similar is in a cathode ray television."

"So… something about Hogwarts and Hogsmeade stops things like that from working," Harry said. "Oh, I see, so they're like electronic switches, and when they were used in everything complicated then nothing would work. But now that things like them are only used in screens and stuff, it's only those things that won't work."

"Cars don't work either," Sirius told him. "Well, I think magical ones do – my motorbike does and it's the same sort of thing – but I've heard it happened once."

He snickered. "It was when I was behind bars, so I didn't see, but apparently it was a Muggle who'd married into a Wizarding household. Came driving down a road that's really not meant for cars, then all of a sudden the engine stopped working. They had to push it somewhere it'd start again, or something."

That made Hermione frown again, drawing circles on her piece of paper with a pencil, then she lifted a foot and stamped it down.

"Spark plugs," she explained. "I think it has to be spark plugs. Those involve a lot of voltage, that's how they make the spark, and valves involve a lot of voltage."

She turned to look towards Hogwarts, though the effect was spoiled a bit by the fact there was a wall and a kitchen in the way.

"Maybe it's something to stop Hogwarts being hit by lightning," Harry's friend said, slowly. "The lightning rod wasn't invented until a long time after Hogwarts was built, and you don't want lightning to hit the Owlery or somewhere like that."

They all considered that, for a bit.

"So… does this actually help?" Sirius said eventually. "We know what might be probably doing the thing, but – and I think you'll agree this is the important question – can we use it to play a prank on someone?"

"I've got an idea," Harry replied. "It's not a prank, so much, but it is a way to use it to surprise people."

Hermione shook her head. "Boys."

"Hey!" Sirius objected. "I'm thirty-seven. Nearly thirty-eight, actually."

"And you're less mature than a dragon half your age," Hermione countered. "I'm calling you a boy because of what you're like, and Harry because that's what he officially is – head boy. According to Dumbledore, at least."

"I was mostly just thinking of getting things set up and having a movie club," Harry explained. "That would be kind of surprising at Hogwarts."

"Hmm…" Sirius said, pondering that. "Not quite as dramatic as I was hoping for, but a good start. What about playing a film in the Great Hall during the Halloween Feast?"

Hermione put her hands on her hips. "Are you actually trying to become the oldest person ever to get a detention at Hogwarts?"

"Well…" Sirius replied, thinking out loud. "Not until you said it."

Harry's only lesson on Halloween itself was Transfiguration, in the morning, and after that the rest of the day was free.

Or, almost free.

Dumbledore asked him to help make sure that the decorations were up to par, which was definitely something Harry could help with – mostly that just meant checking on the work the elves had done, but the Great Hall also needed a little something extra and in this case that meant lifting the cages full of sugar bats up so they could be released at the beginning of the feast.

Harry spent about five seconds wondering whether he should use his wings to get up to where the sugar bats had to go, then thought better of it and went to get his broom.

It wouldn't do to end up sweeping them away with wingbeats just after putting them in place, after all.

Then one thing led to another, and Harry ended up helping with getting ready for Halloween for about half the afternoon. It was mostly little things, and individually they didn't seem like they'd take very long, but by the time Harry was done it was nearly five and he had to go back upstairs to get himself ready.

After last year and the Dumbledore costume, Harry thought it was a very good idea to dress up for Halloween again. Some of the others were doing the same, including a lot of the people Harry knew closely, and while it wasn't exactly a standard thing there were still plenty of costumes on display.

Hermione had dressed herself up as a Victorian explorer, complete with pith helmet – which was just a reminder that being more than halfway through a NEWT in Transfiguration meant that you weren't very limited in what costume you decided to go for – while Ron had opted for the classic Sherlock Holmes look, with the deerstalker hat and pipe.

For reasons Harry couldn't quite divine, Ron had opted for a pipe that blew big colourful bubbles. For reasons that Harry had no idea about at all (apart of course from the perennial it was a funny idea, which was as good a reason as any of course) he'd also made himself the exact same outfit but for Nutkin, so he could turn up in costume in his Animagus form instead.

Dean and Colin had teamed up, going with a matched pair of severe black Muggle suits and sunglasses, and Harry had to ask what that was in aid of.

"It's a film that came out over the summer," Dean explained. "The funny thing is, you'd almost think it was written by someone who knew a bit about the Wizarding world."

"Why's that?" Ron said, then blew a few bubbles on his pipe.

"The job of the Men In Black is to wipe the memories of people who notice things they shouldn't," Colin told him. "They use these metal flashing light things to do it, and it's aliens not wizards they're hiding, but apart from that it's a lot like Obliviators really."

That actually made Harry wonder something about the costume Ron had chosen, because he wasn't entirely sure how much wizarding culture was aware of the Sherlock Holmes books to begin with, but then again he supposed maybe Hermione had suggested it to him.

"Is there some kind of rule about coming in costume that I didn't know about?" Kayleigh asked, a bit nervously. "I know that only some people are in costume, but I thought maybe everyone else just hadn't put them on yet…"

"It's optional," Harry said. "Just an idea that came up last year, and more people are doing it now because it's kind of… an opportunity to be creative, I think."

"Oh, that's okay," the young witch sighed. "I didn't think I could get a costume together that quickly."

She gave Harry a puzzled look. "Actually, what are you dressed as?"

"That depends," Harry told her. "Have you read the Pern books?"

Kayleigh shook her head, mystified.

Harry nodded to her. "That's nothing to be worried about. In that case, I'm dressed as my Patronus."

"...you can do that?" Ron said. "Why didn't I think of that?"

"Ron, did you somehow manage not to notice that Harry is completely covered head to toe in white?" Hermione asked. "Honestly."

"Oh, I noticed, I just wasn't sure which of the many possible reasons for doing that Harry was going with," Ron explained himself. "He could have been going as a ghost, for example…"

The Quidditch captain trailed off.

"...admittedly, that's the only reason I can think of, but it's not the only one there has to be," he continued. "How many white dragons are there?"

"That's not the first question I have today," Flopsy said, her voice slightly muffled. "My first question would be, how exactly did Mopsy convince us of this?"

Harry looked to see what she meant, and had to stifle a giggle.

The Barlos girls had gone for a bit of a meta-costume, which was that both Flopsy and Cottontail were wearing fake-looking papier-mache giant dog heads. It looked like someone had tried to dress up a normal dog as a three-headed dog, and done a pretty good job all things considered.

"I'd assume it's my persuasive powers," Mopsy mused. "That or it's because it was actually Cottontail's idea."

"You've got to admit, it's funny," Cottontail defended herself.

A sort of clattering sound came from up the boys' staircase, getting gradually louder, until someone clad head to toe in armour emerged.

"Afternoon," Neville said, raising the visor. "That's pretty impressive now I see it, Harry, how did you do it?"

"Colour changing charms for my robes, those were easy," Harry listed off. "And I charmed them tighter so they weren't so obvious. Then the rest is, basically, flour with sticking charms."

"That's going to some effort," Neville nodded. "By the way, Harry, thanks again for the sword, it kind of completes the look."

Ginny was coming down the girls' staircase as he spoke, and she visibly did a double-take.

"How is that remotely practical?" she asked. "I get most of the costumes here, but a suit of armour? Those things weigh a ton!"

"It's actually not that bad, once you're wearing it," Neville replied. "Besides, I came up with a cunning plan for how to get around without all the extra weight."

He collapsed in on himself, leaving Lapcat standing there. Without the armour, of course.

"That would do it," Ginny decided.

Harry estimated that about one in six of the people in the Great Hall were actually attending the Halloween Feast in some sort of costume.

It was quite heavily biased towards the people Harry knew more closely – most of the Unusually Shaped Society members had some kind of costume, and of course there was everyone who Harry came down from Gryffindor Tower with.

That included Ginny. She said she'd got the idea a bit late, and she wasn't sure of how well the result had gone, but as far as that went Harry thought it was quite good – seeing as she'd made herself a green suit and green bowler hat, and dressed as the Minister for Magic.

"I don't think I'm going to bother with trying to act like him," she said, as they sat down. "But given Percy, I think I could do a pretty good job if I wanted…"

Some of the other costumes were significantly more technically impressive. Isaac and Xenia had obviously got some pretty high-grade help from someone in Slytherin (Harry thought it was two someones, but he couldn't be sure) and had come dressed as one another, Isaac looking out through eyeholes in the human-shaped-torso balanced sort of unsteadily on his shoulders while Xenia was wearing an invisibility cloak to make her own head and upper body disappear in service of the illusion. That did make the constructed griffin-head look like it was in roughly the right place, though Harry had to wonder if maybe they'd overdone it a bit.

Admittedly, he was thinking that when there were visually-perfect duplicates of Albus Dumbledore and Professor McGonagall at the Slytherin table, courtesy of the Smiths and more than a touch of glamour, and when – in a reference which Harry was sure he should get – June had expanded herself to twelve feet tall and coloured herself vivid red.

Then there was Luna, who'd come as a fire – the flames constantly licking up her outfit, almost concealing her. But that was Luna.

"Allow me to say, welcome, to all students of Hogwarts attending the Halloween Feast!" Dumbledore said, expansively – having turned his beard rainbow again, possibly for the occasion. "And to certain other people who also appear to be attending the feast, hello, and do you know where some of our missing students are?"

That prompted a ripple of laughter through the hall.

"I have only two things to say to you all, and I will say the second thing first," the headmaster went on. "Second, after dint of considerable research which will doubtless earn them all some kind of honorary sixth-year pass in Muggle Studies – not, alas, that that means anything – Messers Sirius Black and Remus Lupin, late of this school, plus a number of Mr. Lupin's relatives, have managed to get enough Muggle technology working at Hogwarts to allow us all to watch a Muggle film. It will be in here after pudding is finished, though of course I will not insist on anyone watching it."

That led to some confused muttering, and after a minute or two Dumbledore went on.

"First," he continued, "eat up, please."

The Halloween Feast appeared with a clap of his hands, and he sat down as people started taking their first servings.

"Sorry, did he just say that your godfather got Muggle stuff working at Hogwarts?" Seamus said, baffled. "How?"

"It's more… something we've been working on a bit at a time for ages," Harry clarified.

He took himself a slice of quiche, which was mostly cheese and onion flavour but which had pumpkin-shaped veins of orange flavour running through it. "At first we noticed that watches and stuff worked, then I got a Game Boy as a joke present and that worked, and after that we've kind of gradually been making a list. Hermione thinks she finally got it worked out, though."

"I think it's got something to do with lightning," Hermione explained, which was an extra detail Harry himself hadn't heard yet. "Hogwarts: A History is terrible with some of the spells on the castle, though, and trying to unfurl the wards with one of the special spells made for that kind of analysis is harder than you'd expect because the whole thing's been made deliberately hard to understand… more than once."

"Why would anyone do that?" Ginny asked, then held up a hand. "Wait, no, disregard my previous statement. I realized as I was saying it."

She doffed her bowler had. "Of course, you wouldn't want someone trying to attack Hogwarts to work out how to get around the defences."

"Wouldn't you just do that everywhere, though?" Ron guessed. "Because you never want someone to be able to work it out? Wouldn't those tools be useless, then?"

"That's a lot of the skill to it," Harry said, glad to be able to contribute with some of his own reading. "But what hurts with Hogwarts is that the making-it-all-confusing is like… you can unpick it, with time, but what's happened with Hogwarts is that someone's made it confusing, then more spells got added to it, then it got made confusing again… it's like some of it is in one code and some of it is in several."

He shrugged his wings. "Hogwarts is really confusing because so many people have worked on it over so long, most places got worked on once or maybe twice and then left. The magic might have gone a bit funny anyway, but Hogwarts has just got weirder and weirder."

"There's a true statement if ever I heard one," Seamus admitted.

He prodded a sort of cylindrical lump of black, gloopy substance with his fork. "Any idea what this is?"

Harry inspected it himself, then took a little bit with a spoon.

"Is it one of your things, you think?" Dean checked.

"There's no flag," Harry pointed out, then shrugged and licked the spoon.

It turned out, as he announced, to be treacle, in the same way you could have a treacle tart.

"But isn't that stuff sort of liquid?" Hermione said, looking more closely. "It should have flowed off."

Harry bit the bullet – metaphorically speaking – and cut a slice.

To their surprise, the treacle turned out to be a thick layer – an inch or two – around a core of tightly woven pastry, and the cut marks remained just as sharp after a minute as when Harry had first made them. It didn't really explain the situation, at least until Dean snapped his fingers.

"I know what it is," he explained. "The House-Elves must have heard about upside-down cake. That's an inside-out treacle pie."

They contemplated that for a few seconds.

"I do believe you are correct," Ron said, and blew a few bubbles on his pipe. "Is this where I say the bit about eliminating the improbable and leaving the impossible?"

"It's meant to be the other way around, but this is Hogwarts," Hermione conceded.

Once everyone was fed and watered – or, in the case of many, juiced – the plates of food faded away, to be replaced with large buckets of popcorn.

"I would like to again remind everyone-" Dumbledore began, and then the sugar bats were released.

Harry hoped he hadn't made whatever mistake had resulted in that, but the net result was several minutes of laughing before finally all the bats had landed or been caught or disappeared into the night.

"As I was saying," Dumbledore re-commenced, once the noise had died down. "I would like to remind everyone that there is to be a film in a few minutes. There is, of course, no obligation to watch it, though I will remind you that it is Saturday tomorrow so you will hopefully mostly not need to get up early."

He turned to look in the direction of Aberforth. "Was that all right? I'm not sure how to word it so that I'm not actually encouraging bad behaviour."

Unfortunately – or, unfortunately if Albus hadn't planned it, and Harry suspected he had – he'd spoken loudly enough that everyone could hear him, which prompted more giggles.

"In any case, without further ado, I'll hand over to Mr. Black and Mr. Lupin, who will be setting things up," Albus concluded.

A few people did get up and leave – Professor Snape among them, Harry noticed – but most decided to stay, through the few minutes while Remus piled the equipment on a conjured table and Sirius made a big white screen which he stuck to the wall over the exit to the Great Hall.

It took four Sticking Charms on the corners to make sure it didn't flap around much, and by the time that was done the projector was wired up, sorted out and facing the right way.

Then Remus pressed play, and the movie started.

Harry hadn't actually been involved in picking the film, but Dean and Hermione had (on the grounds that they'd seen a lot more films) and so Harry was a little surprised when it turned out to be an animated film – one of the Disney ones, though this was one Harry wasn't very familiar with except as a name.

The Sword in the Stone turned out to be about a young boy in a vague sort of Medieval Period Times who encountered Merlin during the events of the King Arthur story, and the strange and silly things that happened as a result.

Some of the things in the story made Harry wonder if the person who wrote it actually knew about wizards, such as the presence of a pet owl for Merlin (and, well, Merlin himself, though Merlin was well known by Muggles as well) but other things only made sense if the bits which were similar were sort of a coincidence or if the bits which were different had been included in spite of the author knowing about magic.

Like the owl being able to talk, or Merlin being able to Transfigure people (including himself) into any animal without ending up altering their minds, or (at least as far as Neville was concerned) the lack of mention of Hogwarts.

Harry wasn't quite sure what to make of a lot of the things that happened in the film, and if Harry wasn't sure then he imagined that a lot of the other students would be considerably more confused – but it was a lot of fun, as well. And the fact there was a pleasant magic-user in the form of Merlin as well as the evil magic user (Madam Mim, who was so happy about being evil that it was sort of entertaining) meant that it didn't just show Muggle attitudes to magic as being negative.

There was a funny bit near the end where Harry realized that one of the bits in the Discworld book Equal Rites had actually been a reference to this film, or to the story that had inspired it, or whatever. The bit where the witch and the wizard were having a shapeshifting battle, which in the film got sorted out by Merlin doing something very clever indeed.

Also, it turned out the young boy was King Arthur, though it wasn't clear if that was because he'd always been a prince or if it was just that he was so nice that he got the position anyway.

And there was a squirrel who was sort of romantically interested in him when he was turned into a squirrel. Which immediately got Harry wondering if maybe she was going to be turned into a human, but if she was it was after the end of the film.

It was the sort of thing he thought he'd do, anyway, if only to have her turn out to be Guinevere.

"I think that went rather well," Dumbledore said, once the film was over and everyone was heading upstairs.

Harry had stayed behind a bit to help Remus pack everything up again, and Dumbledore had wandered over to watch.

"Quite a remarkable piece of equipment," he added. "And to think every Muggle has one of these."

"Well, a lot of Muggles have a television, but they're almost all a different sort," Harry replied. "The sort that doesn't work at Hogwarts… but that sort couldn't be used to show hundreds of people the same film at the same time."

"And a fine choice in film it was as well," the Headmaster said, as Harry helped Remus lift the connected-up projector, video machine and power supply into the same magically expanded box. "I particularly liked the main character."

His eyes twinkled with mirth. "I mean, of course, that fine old wizard Merlin. A man after my own heart."

Somehow, Harry wasn't surprised.

AN:

Suddenly Harry can Apparate. Which simplifies his logistics a bit.

Well, I say 'suddenly'… he had a lesson and everything. But it does make travelling around the place much easier.

Also, while it's largely an American thing, the costume Halloween not directly related to dressing scary was becoming more popular in this time period in Britain and that's good enough for me for these purposes.