I looked up at the house in front of me.

It had three stories, but was quite narrow. The outward bulging bay windows were absent on the ground floor, where the front step was framed with pillars. It had a very organic look, like it had been grown out of black cement. This was a steep contrast to the buildings either side – smart, classic-looking middle-class houses. I walked up to the black oak door and knocked, using the black cast iron door handle. The colour scheme was so imaginative. The dark, moonless night didn't help.

The door was opened by a flustered house-elf with flour all over it. She grinned at me,

"Come in, dear madam!" she said, in a thick French accent. It had always seemed strange to me that such a small, frail, subservient creature should have a voice more suited to the most stereotypic of Parisian women, but it was typical of Joshua Grey.

Josh was the only-half-cracked crackpot inventor who owned the house and elf. It was generally agreed by those that knew him, myself most of all, that he would further crack in time. His neck-length black hair would become white, as it already was in places, and stick out in a mad mess. The beard on his chin would probably remain the same, pointy, tapering away along his jaw, but would grow white and more bristly. And that no amount of healing would ever heal his left eye, on which he wore an eye patch. He had lost it in his younger days, when he was so much more lawless and free.

"Where is he?" I asked the elf, whose name was Hoppy. I came into the hall – to my right was a staircase, leading up onto a shadowy landing. Books were everywhere, in neat stacks almost six foot high in places. They effectively were the walls.

"The master is in the garden, madam, working on it," she said, with a despondent sniff, "Madam, I know it is ill of me to say so, but could you possibly have a word with 'im about all this, or something? I do worry about 'im, sometimes. I often need to remind 'im that it is lunchtime, which is most unlike the master."

"I'm afraid I've already tried, Hoppy," I said, giving her my travelling cloak, gloves and hat. I wiped my boots on the mat.

"Well, I 'ad to ask, you understand. Would you care for a drink of something?" she asked, gesturing to the kitchen.

"I'll have a glass of wine, please," I said, and followed her through.

Even if Josh had known how friendly I was with his house-elf, he wouldn't have minded, for two different reasons. One was that he wasn't like that – a very friendly man, sometimes overly so. And the other was that it was my business to talk to everyone. By everyone, I also mean everything. I pride myself on being the ultimate trafficker of information. I speak Mermish, I'm in contact with the centaurs, I'm a quite gifted medium, and most of the important goblins know me. Even Dementors are willing to communicate with me, in their way. Sometimes, I've even been known to talk to muggles. And anyone who knows anything about house-elves knows that they all talk to each other about what goes on. It's a huge network of gossip and rumour. Sometimes a genuine fact, or better yet a secret, will find its way to me. Even those that know about this highly unofficial network never really know how to tap into it. Both sides of the law pay me fairly handsomely, to be told anything I think they might want to know. That was how I had come to know Josh Grey. Everyone wants to know where they can get a working invisibility cloak, magical map, luck potion or a discreet object of one sort or another. Josh used to provide for them.

After talking to Hoppy for a while, I brought Josh a glass of wine in the garden. These days, he knows that he can trust me – gone are the days when we used to spike each other's drink with truth potions. He was always better at making them than me anyway.

The mysterious 'it' in the garden – narrow, muddy and unweeded – took up most of the space. Parts of it took up the rest. Large cogs, sheets of metal, piles of scaffolding and so forth. Other mysterious objects lurked in the darkness. The thing stood in the centre, like one of those giant muggle 'rocket ships'. Except the lower half was more like a tower, made of symbol-carved granite bricks. I could see a shape moving around, about twenty feet up the thing.

Speculation had been growing, in certain circles, about what it was that Josh had actually been building back here. He hadn't even told me!

Of course, there were bigger things to talk about these days. Voldemort's return, the most recent murder, things like that. Josh's home security was, of course, some of the best. He had spent time in Azkaban, long ago, and it had made him even more paranoid.

"Josh?" I called up into the scaffolding surrounding the thing.

"Is that you?" he called back. There was a clattering, and a length of copper pipe and a small wheel of some sort fell from the structure. Josh clambered down on various ladders until he could see me, peering at me from nine feet up. His wand-tip lit up with a thin, watery light, and gave everything in the garden an eerie shadow. "It is you!" he exclaimed. He was beside me, looking up at the monstrous thing, before I knew it. "What do you think?"

"You still haven't told me what it is," I said.

"No? Well, no! Of course not. Not yet. All in good time. But what do you think, anyway?"

I looked up at the thing. It was only just higher than his house. At the top, I could see what looked like portholes, and a door with a rope ladder dangling from it, into the scaffolding.

"Very male," I observed. He laughed.

"Actually, you arrived just in time. I suppose I may as well tell you after all," he blathered.

"Before you start, I have news," I interjected.

"Oh yes?" he said distractedly.

"Well, to start with, Potter is going out with that Weasley girl."

"The one with the bushy hair?"

"No. I mean the ginger one. Year below him."

"Hardly news," muttered Josh.

"Just a touch of light-heartedness. Her brothers – you know, the twins? New joke shop over in Diagon Alley? – they're still dying to meet you."

"Right," he said. He wiped his brow with the sleeve of his long, white laboratory-type coat he was wearing. Beneath it, he had his usual black trousers and refined pinstripe waistcoat. "I'll get around to replying to their letter, soon. What else?"

"Well, Borgin's been getting visits from Greyback. The werewolf? Maybe extortion, maybe something more. And Scrimgeour's been talking to the Head Banker at Gringott's, but no one thinks it's very much. Olivander might have turned up in Spain, I'm not sure about that yet."

"That doesn't sound like you," he observed, dryly.

"It's just a rumor. I'm looking into it tomorrow. I've already sorted out what I think might be the nearest fireplace to where he was supposedly seen. Anyway, the centaurs are getting very restless, saying there's something important coming up. Some dire event. But then they're always saying that. Dumbledore has been poking around for a few weeks in quite strange places."

"Who's died this week, then? Enough of the pleasant stuff," Josh sighed.

I told him who had died since Sunday, due to Voldemort and the Death Eaters. Three wizards, one by an explosion that had also eradicated a dozen house-elves that had gotten in the way. Three muggle children, two girls and one boy, had been kissed by Dementors. They would now live in Care Homes the remainder of their lives.

Josh sighed again,

"And it's only Wednesday," he observed. I tried to stifle a laugh at this, knowing it would upset Josh. He didn't notice anyway.

"So what's this thing, then?" I asked him, and he immediately perked up again. He took a creased roll of parchment out of the inside of his coat, and unrolled it, showing me.

"See this?" he asked. The piece of paper was huge.

"Yes?"

It was a drawing of what looked like a giant cannon, as big as a house. As I watched, the blueprints animated themselves. The drawing of the cannon disassembled itself and the thing proved to be much more complicated inside. Buried amongst the detailed sketches of mechanisms and machinery was a large prism, simply drawn, pointed the length of the 'cannon'. Complicated mechanisms surrounded the end of it, almost obscuring it. Then the drawing twitched on the paper, and sketched devices started operating. If it had been real, the ground would have rumbled. Complicated pencil lines snaked out of the end of the drawing, the mouth of the cannon, and a mushroom-shaped capsule was propelled off of the edge of the page, out of view. It was followed by a lot of hastily-drawn equations and Arithmancy-like workings that I didn't understand.

"So what is it?" I asked again.

"This is that," Josh said, motioning to the giant object in front of us, but failing to clarify.

"Please explain in depth," I asked, keeping it simple for him. Josh shook his head bemusedly, and turned towards the house.

"Follow me. This could take a while. You'll want to sit down."

His living room was full of more books. On top of the books, there was an occasional object. They looked very much like bric-a-brac. But knowing him, they would all be very unique. The wooden statuette of Buddha, for example, might make you laugh if you tickled it. The stone owl might tell you the odds of getting laid during the course of your average day. The flying goggles would probably let you see through people's clothes. The walls were covered in pages of drawings and doodles. Some danced, some shagged, some walked tirelessly without moving. There was a large glass tank dominating one end of the room, in which two giant snails slimed along amongst huge leaves of cabbage. It looked like their shells, as big as my head, were made of tarnished copper. Three small metal spheres orbited the room randomly.

Josh was packing his black ebony pipe with some of his curious sweet-smelling tobacco, from an ornate wooden box on top of a leather-bound tome. He offered me some more wine, and I accepted. We sat in worn-looking armchairs.

"In the late 1850's," he began, "Victorian wizards experimented briefly with an alternative method of transportation they called Spectromechanics. I won't go deeply into the workings, but they discovered a way of intensifying sunlight, in a system of mirrors, which could be angled through a prism. This would fracture the light, so intense and bright that by now, with the proper enchantments, an object could be pushed along by the resultant spectrum of light. Basically, you can ride a rainbow."

"I see," I mused. I'd never heard of it before, so presumably it hadn't worked very well.

"It didn't work very well," said Josh, proving me right, "Because the violence of the light was hard to control. But I found you could lengthen the control-jib, of course putting more gears into the main slide-shaft…" It was at this point I found myself drifting off, realising he was in fact going deeply into the mechanics. There was such a lot to look at in his cluttered, colourful house that even I found it distracting. I started paying attention again when I thought he might have finished, "…inside the actual lens, thus propelling it up to a hundred times as far. Laughable in retrospect. Focus did become a problem, but it only needs to achieve enough thrust, and the reflective module inside…" He hadn't finished. He burbled on for another minute or two, puffing on his pipe sometimes, before I realised he had stopped talking.

"So, what does that mean, in conclusion?" I asked.

"It means that they weren't ambitious enough," he replied. He nodded to a drawing on the wall, which detailed the phases of the moon and its orbit around Earth. I had a sudden insight into what he thought he was doing.

"You're going to ride a rainbow," I stated, in dull surprise, "to the moon."

"Yes! That's exactly it!" he gesticulated excitedly.

"Are you joking?" I asked. He shook his head,

"Do you want to see?"

"What? We can go to the moon, right now?" I asked, incredulous.

"No no. Not just yet. Hardly the right time of the month. I can't even see the moon, to aim. A thorough grounding in astronomy might have come in handy, of course, but it was never my thing. I've been reading up, of course."

"I see," I said again. That didn't sound very good. Surely someone going to the moon should be an expert? But I didn't raise the point, as Josh had got up and was walking back into the garden.

"Come on!" he called back.

In the dark of the night, I couldn't make out anything of the drawing in the construction now in front of me. While in the drawing the whole thing had pointed sideways, this pointed upwards. I smirked at the phallic metaphor even more.

"Like I said," he was saying, "We don't really need the sun."

"We don't?"

"I knew you weren't listening," he grinned in the dark, and pulled out his wand. The tip lit up again, and he strode towards the huge machine. Moving a pair of wooden planks out of the way, he thrust his wand into a gap in the stone wall.

Instantly, all of the symbols carved into the stone started to glow white. He extracted his wand, and they remained glowing. He walked back to me, and rolled up his sleeves. He was looking very excited.

"Have you done this before?" I asked him.

"Only with very small trial versions. The first time I've tried it with this size of Regenerous charm, really."

"How have you kept all this secret from your neighbors?" I asked, suddenly curious, looking at the gardens either side of his. A large lavender bush poked over the fence on one side, and a holly bush skulked low on the other side. The top of a set of swings and a washing line were just visible. The monstrous machine in his garden towered over them like a monolithic giant.

"Just general enchantments," he shrugged, and waved his wand. The cogs ground together suddenly, and then started moving more easily. He waved it again, and there was a sudden stream of incandescent light inside the huge thing, which looked prism shaped. The prism started to glow brighter and brighter, silhouetting the machinery and contraptions in front of it.

And then the sky was colour. Into the sky, seven brilliant beams of light shot away into the clouds. It was brighter than daylight. I looked at Josh, and there was green light shining on his face. On me as well. To my right, the back door of his house was bathed in blue, and the piles of old stone on Josh's far left were shining in the yellow light. The clouds, high above us and steeped in darkness until just now, were glowing in all the seven colours. I imagine the windows of the houses for miles around were probably reflecting this brilliant sight. All of the quiet little London suburb was probably wondering where the red, yellow, orange, green, blue or purple light was coming from.

And then it was gone, and the shadows came back. Everything was pitch darkness for a little while, until my vision returned. Josh rubbed his good eye, and turned to me, grinning expectantly. For the first time in my life, I found myself not knowing what to say. Josh seemed to know this, and nodded,

"It works!" he enthused, a huge grin on his face. "We could go to the moon!"

He scurried over to the scaffolding, apparently forgetting that I was there. He was muttering to himself.

"What about getting back?" I called up to him. He looked at me, somewhat surprised, confirming my theory he had forgotten all about me, about everything, in his excitement.

"Simple in theory," he replied. "A smaller engine inside the pod itself. It's just a matter of getting out of earth's gravity, like I said." I was going to ask more, but something else pushed that train of thought off the track completely,

"That little display just now," I started.

"Yes?"

"Surely the muggles would have noticed that?" Josh seemed temporarily deflated, bless him. But then he shrugged, and thoughtfully said,

"The muggles probably only think it was a firework display or something. I'm sure it's fine."

Unfortunately, at that moment, Hoppy the house elf appeared next to Josh, tugging at his sleeve.

"Yes?"

"Master Grey, sir, there are some men from the Ministry of Magic at the door. They do not look 'appy. They say something about breaking the Statute of Secrecy, which is one of the fundamental cornerstones of our world. With all due respect, Master Grey, I told you so."

"Ah," said Josh, thoughtfully. He looked at me. I looked at him, giving nothing away in my face. He would find no sympathy in me. He had got himself into his own mess, once again. Just like before, when the time-turner he'd built had killed some foolish wizard, earning Josh imprisonment in Azkaban. But to my surprise, Josh Grey only shrugged again, and a wry grin spread across his face. "Even Galileo had his bad days."