Harry stepped up onto the second rung of the security railing and reached out, stretching as far as his arms could go. Gripped firmly in his right hand was a crude sort of fishing net, which he proceeded to swipe and swing, taking great care not to topple over the edge. For it was a long way down to the streets far below. Almost a thousand meters some guessed. It was a height almost impossible to believe, considering it had been hollowed out deep beneath the surface of the Earth, which was yet higher still.

Harry looked out at the huge towers The Spike and The Pickle, whimsically named after sister buildings in surface London, and fought a sickening bout of vertigo that threatened his balance. His goal was a special sort of moth which had evolved down here. They fluttered and snapped, thousands of them, around the hundreds of giant glass globes which made up the Light Deck, and provided illumination to the city down below. The moths had found a way to absorb the light, and then change it to different colours as they tried to attract a mate. It was the prettiest thing, to watch all the reds and blues and golds flash and sparkle above him.

So Harry wanted to catch some, trap them in a jar, and give it to his mother as a going away present.

For he was now growing fitfully excited about his adventure to the world above. It had taken a couple of weeks to truly adjust, to learn to bear the secrets his parents had now begun to expose him to. But, once he had, the anticipation began to bite at him like a persistent midge. He was fascinated as his mother showed him her magic wand, and utterly astounded as she demonstrated it, producing a pretty silver doe from its tip, which she called a Patronus.

But even that couldn't prepare him for his father's magical display. He left Harry completely speechless as he transformed himself into a powerful stag, before chasing Harry playfully around the garden of their large estate, finally changing back and explaining to Harry that he was something called an Animagus. Harry had so much to learn, he knew, and the realisation vexed him greatly. It was a concern he expressed to his mother, as she was studying ore samples that the alchemists from the Institute of Precious Metals had sent over for analysis.

"I ... I bet I'll be the worst in the class," Harry mumbled. "I'll be so far behind everyone."

"No, you won't be," Lily replied supportively. "Lots of students who attend Hogwarts come from Muggle backgrounds. And even those of magical families don't have much of a headstart. If you just buckle down and study hard, you'll get along just fine."

"I don't think I'll ever be able to do the things you and Dad can," Harry grumbled. "Creating stars from your wand is all very well, but it seems a long way to go to be turning thimbles into tea cups."

Lily chuckled and flicked the magnifying lens from her eye. She beckoned Harry to stand in front of her, then took his shoulders firmly in her hands and smiled warmly at him. "Now, you listen to me, Harry Potter. You are a wizard, and a thumping good 'un, I reckon, once you get trained up a bit. Don't expect to learn everything straight away. Just take it one step at a time.

"I tell you what, next week your father has some work to do on the surface. We'll arrange for you to go, a sort of Bring-Your-Child-To-Work day. Then, your Dad can take you to buy some spell books and things, to get you ready for Hogwarts. What do you say to that?"

Harry's eyes lit up with fervour. "Ooh, can I?"

"Yes, sweetheart," Lily beamed. "We'll see if we cant give you a headstart on all the others. But I expect you to learn all the books by heart if I let you go, and I'll test you on them to make sure. Deal?"

"Deal!" Harry cried. Then he frowned. "But, what about Dad? Wont he be seen?"

Lily's eyes twinkled. "Oh, don't you worry about that. Your Dad will have that little issue covered."

Harry had to wait twelve days for his mother to fulfil her promise. On Saturday, he was ready at eleven o'clock. There was mist and frost, which wasn't unusual for any time of the day down here. Little droplets of it clung to the astroturf lawns and the wax resin trees, for it was impossible to grow real plants down here, so far away from the sunlight as they were. Nobody had yet been able to explain the frost, or the clouds which sometimes formed and wreathed the Light Deck in a dark, foreboding fog. There were even old stories that said there had been lightening down here once, but nobody could remember if that was true or not.

Harry and his father, James, made their way through the deserted streets to the Central Underground Train Station. Quite why it was called an underground station had always confused Harry, for everything down here was underground. He supposed it was due to the connection to the famous Tube network of London, which linked up to Annwn roughly following the M4 motorway corridor, which ran along the surface high above. They arrived at the station around half an hour later and huddled together in the shadows of the platform to wait.

At exactly seven minutes past twelve, a train sped into the station. This train didn't usually carry passengers; it was a special train that brought cargo from several subterranean lakes that had been converted for fish farming. The railwaymen called it The Flying Kipper. Occasionally, however, The Kipper would head to the surface to bring back special fish for a banquet or something, if important people were visiting Annwn.

It was also the easiest way to sneak hidden wizard boys to the surface without drawing any attention to them.

Harry and James waited in a storage depot as The Kipper unloaded its cargo. When the coast was clear, the fireman gave James the signal, and he darted from the shadows, dragging Harry along in his wake. James bundled his son into an empty cart, a heavy door slammed, men hustled and bustled and swore, the signal light shone green ... and The Flying Kipper was ready to go.

The wheels screeched and groaned, turned slowly and the train began to move, quickly picking up speed as it gunned into a tunnel and began the steep ascent to the surface.

Harry felt the thrill of adventure pound in his bones, even forgetting his usual illogical fear of the dark, as the lights of the city were left far behind. He pinned his ear to the wall of the cart, listening to the crunch of wheel on rail, dizzying himself with fantasies of what he would find when they emerged above. He turned to his father.

"Dad? What's it like up there?"

"Very different to what you know," James replied from the thick gloom. "It's very bright. That's the first thing you'll notice. It's Summertime, too, so you'll need to wear sunglasses before you step out into the world."

"Why?"

"Because, you haven't seen sunlight in a decade," James explained. "If we aren't careful, you could go blind."

Harry gulped, and swallowed a host of new questions that had suddenly occurred to him. So he decided to stick to the ones he had already been thinking about.

"Can you really buy spell books and wands and things up here?" Harry asked.

"If you know where to look," James answered. Harry couldn't see him, but he could almost feel his father grinning smugly from across the train cart.

The journey to the surface was slow and steady, taking almost a full hour. By the time the train began to slow, Harry was beginning to grow uncomfortable on the cold wooden deck of the cart. The train eventually came to a stop, and James' friend, the fireman, let them out and onto a lonely little station.

Harry frowned. "We're still underground."

"Yes, son," James replied. "It wouldn't do for people to see a train disappear into the Earth all the time, would it? So we had to build a platform in this old mine shaft and take a lift to ground-level. Come on, it's this way."

James thanked his friend for the trip, and guided Harry a short way along the crude platform to a rickety old mine elevator. It had once been purple, but age and dirt had faded it to something closer resembling midnight black. Harry stepped inside and his father closed the cage behind them. Then he turned to Harry.

"Here, take these." He proffered Harry a pair of dark-lensed glasses. "They are called aviators, and they will make you look pretty suave and cool. Not as cool as me, though, not when I'm wearing this."

James smirked and pulled a most bizarre garment from inside his jacket. It was silvery, and flowed like liquid rather than fabric. Harry had never seen a material like it.

"What is that?"

"I could tell you," James replied, his eyes sparkling mischievously. "But it would be so much more dramatic if I just show you."

And with that, he threw the bizarre cloth over his shoulders ... and promptly disappeared.

Harry gasped, his eyes bulging as they went very round. "Dad? Where are you?"

"I'm still here, son," a disembodied voice replied. That smugness was almost unbearable now.

"Dad!" Harry whispered, awestruck. "You're invisible!"

James pulled the hood of his garment down and grinned at Harry. "Pretty cool, huh? This is my Invisibility Cloak."

"Wow!" Harry replied in disbelief, punch-drunk as he stared at his father's head apparently floating in mid-air. "That's amazing! Can I get one?"

James chuckled. "They are very expensive, Harry. Tell you what, what you go to Hogwarts I'll let you take it with you. See if you cant impress all those new friends you're going to make."

Harry felt a cosy warmth rise in his chest. Friends ... he'd always wanted some of those. He was looking forward to that part almost as much as he was casting his first spells.

But, as his mother had suggested, one thing at a time. So he pushed his indecent enthusiasm down a moment and followed his father out of the mine elevator and into the dazzling daylight of the late afternoon.

"Welcome to Wales, son."

Harry was instantly glad of his new sunglasses, for even through the tinted glass the light was painfully bright. Harry winced a little as it stung his retinas, but he was determined to keep his eyes open, to drink in all the sights of this brand new world. One thing he hadn't expected was for the light to be so warm. It was a lovely sort of heat that crossed his face, quite unlike the type produced by the the giant boilers down in Annwn.

But it was the view that truly warmed him. Gorgeous green fields and valleys sped away from him in all directions. There were hills and mountains in the background, and a hint of blue from the sea just peeping over the horizon. There were dots of white where sheep grazed merrily on the hills, and clumps of dense green forest, and the pale yellows of wild grasses, all kissed beautifully by that burning sun already high in the Eastern sky.

Harry huffed crossly. "Dad ... you and Mum lied to me ... it's not savage up here, it's wonderful. No ... it's paradise."

And in that moment, Harry thought he'd rather not go underground ever again. Not when there were such sights to be seen in the wide world above.

"Come on, Harry," James cajoled. "Let's go somewhere to make you even crosser at your Mum and me."

With that, he threw his hood back on, took Harry's arm in his invisible hand, and jerked him away in a swirl of sound and colour. Harry felt squashed, as though he were being squeezed through a very narrow tube. His head span, he felt sick, and just when he was convinced he was about to see his lunch again, he felt his feet slam in to the hard stone of a London pavement.

Harry blinked to regain some sort of composure and looked furiously around.

"What the hell was that, Dad?"

"It's called Apparating, and it's a form of magical travel, essentially teleporting," James explained in a low mumble. "But Harry ... now you are out in public, it will appear to everyone else that you are on your own. I wouldn't make a habit of talking out loud. Even in the magical world, talking to yourself is generally seen as a bad sign, son."

James chuckled at his own joke, and Harry fought the urge to kick his father in his invisible shins. He scowled at the patch of air that he knew his father to be, then flicked his eyes to the peeling awning of the grubby little building to their left.

"The Leaky Cauldron," Harry read. "What is this place?"

"A ancient public house, and you wont find a finer establishment for getting wonderfully drunk in," James replied fondly. "It's one of the most famous in London. Now usually, the place wouldn't allow children in without adult supervision, but as the new term at Hogwarts is just about to start, some very slothful students will have left it to this last weekend to stock up on their school supplies. So The Cauldron generally relaxes its rules. Just head inside, take a Visitor sticker from old Tom behind the bar. Tell him that you are Muggleborn and don't know how to get on to The Alley. He'll do the rest."

Harry followed his father's instructions. The little pub was crammed with shoppers, many with children in tow, which probably explained the harassed expressions on the faces of the waitresses running about with hot plates of food and foaming tankards of ale. For a famous place, Harry thought it was rather dark and dingy. But he looked around in wonder, trying to soak up every image as though his brain was some weird sort of sponge. He didn't want to forget any of this when he was back in Annwn.

Old Tom was busy serving at the bar. A large family was stood nearby waiting to be seated, and they were growing restless. The mother, a rotund woman, was busy clipping one of her children around the ear, to stop him flicking peanuts at another of her children, who was furiously rubbing a patch of dirt from his nose. Harry sucked in a shocked breath, as he saw a third child dart from behind his mother's big belly. This wasn't a shock in itself, but the fact that he was identical to the first boy made Harry simply goggle at the lot of them.

And there were a lot of them. Five children in total, all with blazing red hair. Four boys and one girl, who wore a haughty, weasely-type of expression. Harry imagined she was a troublesome child, very difficult to please. He wasn't sure she was the type of friend he hoped to make when the time came for him to attend school.

"Hogwarts, dear?" a stern but kindly-looking older woman asked, startling Harry as he ambled around looking lost. "You must be Muggleborn. Trouble getting onto The Alley? Come along, chop, chop. I'll show you the way."

Harry followed obediently, as if he had no choice in the matter. The woman led him to a small area at the back of the pub. She reached into her cloak, an emerald green one, and drew out a magic wand. Harry watched, transfixed, as the woman tapped her wand against the brickwork in a practiced pattern. Harry tried to follow it, but the bottom suddenly dropped out of his stomach as he watched the wall churn and move and become a huge archway onto a truly wondrous sight.

"Welcome to Diagon Alley," said the stern woman, looking down at Harry. "You will be okay from here. Madam Malkin's is just there, and Flourish and Blotts will have all your standard spellbooks. If Quidditch is your thing, I understand the England International Team are holding an autograph session at the supply shop, before they head off to the World Cup in Canada next month."

Harry gulped and looked around. He was about to move off when a little poke in his ribs reminded him of his manners.

"T-thank you," Harry mumbled. "But, I don't have a Visitor sticker. Could you please tell me where I might get one?"

The witch smiled down, her expression softening in the face of Harry's nervousness. She looked over to an even older witch, who was just about to enter the arch in the opposite direction.

"Augusta, are you done for the day?"

"Yes, thank Merlin," the older witch replied. "My poor feet can take no more."

"Perfect. Can we steal your Visitor pass? This little boy has lost his."

"Of course," the old witch replied. "Neville! Come here!"

A small boy with a round face trundled up and stood chaste at the old witch's side. She reached down and tore a grey sticker from the t-shirt he was wearing, before planting it firmly on Harry's chest. Harry felt slightly winded by the impact, but managed to blurt out a stunted little 'thank you', before setting off down the street.

Harry wished he had about eight more eyes. He turned his head wildly as he walked, trying to look at everything at once. He was mesmerised by the shops, the things they sold, and the people buying them. There were shops selling racing brooms, and ones full of owls and mice, and yet more with big buckets in the windows full of bats eyes and dragon livers. There was simply too much to take in, and Harry was reasonably convinced he had forgotten more in the last five minutes than he had in the rest of his life put together.

"In here," said a low voice suddenly in his ear.

Harry looked up at a big awning of a book and quill above Flourish and Blotts bookshop. He opened the door and ducked inside. Luckily, the shop was very busy. Harry was able to move unnoticed to a shelf deep in the back, where he could whisper to his father without drawing attention.

"What should I get?" he breathed, when he was quite sure there was no-one nearby.

"Look for The Standard Book of Spells," James replied quietly. "And Magical Theory. You wont be able to cast spells, as you cant have a wand yet, but your adeptness with runes is something we can explore. Magical Theory covers basic ritual casting and circle creation. Your mother doesn't approve, but ..."

"Here it is," Harry chimed brightly.

He held up the heavy tome and showed it to his father. Or, at least, where he expected his father to be. A quick scout of the shelves later and Harry had located The Standard Book of Spells, too. Then, his eye fell on a book that seemed to just jump out to him.

"Hogwarts: A History," Harry read on the cover. "Can I get this one too, Dad, just for some background reading?"

"Throw it in your basket," James chuckled. "That will do for now. We wont be able to carry them if we get many more."

Harry bundled the books into a mesh basket he picked up from a rack nearby and began to approach the till. Then, a horrible thought struck him.

"Er, Dad, how am I going to pay for these? I don't have any money."

James guffawed again, and Harry felt the cool fabric of his father's Invisibility Cloak flow over his wrist. A moment later, and several large coins slid into his hand.

"These are Galleons," James explained, as Harry examined the heavy gold coins his father had given him. "Just hand them over. Tell them to put any change into the Hogwarts Hardship Fund."

"What's that?"

"Not all magical families are so fortunate to be as well-off as we are," James replied. "The Fund provides financial assistance to the most needy of students, to help with school supplies."

Harry nodded and made his way to the counter, where he paid for his books. The shop assistant thanked him warmly for his generosity, as he popped a few silver coins and little bronze ones into a tin next to the till. Harry frowned as he listened to the sound. It was disconcertingly hollow.

"Oh, I didn't know anyone actually put money into those things," came a drawl from behind Harry. "I always assumed it was a sort of joke."

Harry turned to see a man with a sour face and very long, ruler-straight white blonde hair standing close behind him. He carried a very handsome cane with an elaborate silver serpent set into the hilt He looked down at Harry with a disapproving sort of snarl.

"You really oughtn't waste your gold on such - ahem - charity," the man drawled on. "If I had my way, they wouldn't even let the sort of riff-raff who rely on handouts attend an institution like Hogwarts. When I join the Board of Governors next year, when my son begins his schooling there, I will petition strongly for a change in the law."

"Now, now, Lucius, be kind," said a tall witch from behind him in the line. "We all need variations in the gene pool in order to survive."

"If you allow hybrids to breed with pedigrees you inevitably get mongrels, Miss Sinistra," the man Lucius scoffed. "No use encouraging the dilution of Magical blood with Muggle mud, I say."

Harry had heard enough. He scuttled off angrily to his invisible father, who had to hold a hand to Harry's shoulder to diffuse his discontent.

"Dad? How much more gold do you have on you?" Harry hissed under his breath, watching as customer after customer took their change, not one depositing a single coin into the collecting tin.

"A little. Why?"

"Can I have it? All of it?"

"What for?" asked James, curiously.

"Can you just give it to me? Please?"

"Okay."

James slipped a dozen more gold coins into Harry's hand, and he made his way back to the till again. He ducked under the flowing robe of a sallow-faced man with lank, greasy hair and reached up towards the counter once more.

"Excuse me," Harry grumbled as politely as he could manage to the scowling wizard, who frightened Harry a bit, reminding him forcibly, as he did, of a vampire from one of his comics.

Harry ignored the sneer, and dropped all twelve coins into the Hardship Fund tin. Then he retuned to his father, who steered him surreptitiously from the shop, with an approving pat on the shoulders.

It wasn't until they were clear and quite alone, at the corner of a more subdued street called Inphorm Alley, that Harry burst free with questions.

"What was that about, Dad? All that business about Magical blood?" Harry demanded.

James sighed heavily. "You will soon learn, son, that Magical society is quite blatantly denominated. At the one end of the scale, you have Magical families that can trace their lineage back many generations, and they are called Purebloods. While at the other, magic seems to flourish anew in people of non-magical parents, and they are known as Muggleborns. Then there are all sorts of other configurations in between."

"And I suppose Purebloods think they are better, because they've had magic in their families longer?" Harry riled.

"That's the long and short of it, yeah," James replied. "But it's all a load of nonsense. My family is Ancient, and that makes me a Pureblood, but the most powerful witch I ever knew had Muggle parents. She was the best in my year at Hogwarts by a million miles. Did more incredible things with magic than I could even dream of doing."

"I wish I could have met her," Harry grumbled. "She sounds great."

"Oh, she was ... and you can," James quirked. "I married her, after all. So when we get home, just call out for Mum and she should answer you!"

Harry gasped in surprise. "Mum had non-magical parents!? But how? I've seen the things she can do! They are amazing!"

"Precisely," James replied, firmly. He took Harry by the shoulders and turned him to face the air where James was magically hidden. "Which is why blood has nothing to do with magical skill or what kind of person you'll grow up to be or anything important like that. Remember that, Harry. If this trip teaches you anything, let it not just be the content of those books. Let it be that all people, magical or half-magical or not magical at all, are all equally valuable. Some people will try to tell you otherwise ... but I trust you to decide on the wrong sort for yourself."

Harry gulped hard at that. "Like the man at the book store? He was the wrong sort, wasn't he?"

"That man was of the worst sort," James growled. "He was a known supporter of that Dark Lord we told you about. Claimed he'd been brainwashed when it was all over, so Sirius says. Don't believe a word of it. Lucius Malfoy didn't need any cause to turn dark ... it's as natural to him as breathing.

"Anyway, let's get you back home. If I hang around here much longer, I might be tempted to go back and curse that conniving, bottle-blonde traitor from some dark alley or another. And your Mum always wanted first refusal on blasting him to bits with her wand. I don't her to be cross with me, for taking that pleasure from her, now do I?"