As much as Harry had enjoyed the time with his friends (and, despite Fortescue's having been boarded up, they had managed to find another ice cream parlor that was nearly as good), he was happy to return to Grimmauld Place. While Sirius had, rather jokingly, forbidden studying and lessons during the weekends of Harry's summer holiday this year, Harry was looking forward to looking over his new books for the following year. He was glad that he would only be taking five courses, even though he rather suspected he would be working nearly as hard this year as he had last year.

The work load never lessened, only increased, and Harry felt a twinge of longing when he thought that an average of about two hours a night in his third year had been a lot. He might not be up until past midnight every night this year, but he would still be studying at least as hard as in his fourth.

He was rather glad that there were almost four weeks remaining of the summer holidays.

Now, having eaten a considerably smaller dinner at Grimmauld Place than the lunch several hours earlier, Sirius and Harry sat side by side in the sitting room, Pensieve in front of them.

It was becoming Harry's favorite time of the day.

"I have two memories to show you, and I think you'll see the link between them easily enough," Sirius began, carefully extracting the first and sending the silvery wisp into the basin. "You know a bit about each of them from myself and Remus, but, as you can tell, experiencing them is something new entirely."

Harry grinned. "Shall I guess?"

Sirius laughed. "Sure."

"The Marauder's Map," Harry answered.

Grin deepening, Sirius simply replied, "You'll have to wait and see."

He pressed his wand to his head and a second sliver of wisp emerged. A thought occurred to Harry.

"Sirius, could I show you come of my memories? Not today, I mean," he added quickly, "but maybe, before the end of the holidays?"

Sirius went quiet, and then said, slowly, "I'd love that, pup." Harry gave his godfather a small grin, and Sirius squeezed his arm. "On the count of three, then? One, two, three!"

The scene was the Gryffindor dormitory. Harry knew it well enough, having spent five school years there. The decorations were rather different, and Harry could see that at least one of the bedspreads had changed since Sirius and his dad had been at Hogwarts, but almost everything else was the same.

Sirius, looking rather younger than he had in Snape's Pensieve, but hardly as young as when he'd first boarded the train, paced back and forth, a look of intense concentration on his face. James had his arms folded across his chest, his brow furrowed, his hair even more untidy than the last time Harry had seen him. Peter, Harry noticed with mild annoyance, was there as well, with a look of respect on his face, and so was Remus. He looked rather paler than usual-perhaps he'd just transformed?

Harry's attention went to one of the tables, on top of which sat...

Two identical mirrors.

He felt his heart begin to race.

"You know," Remus pointed out, in his mild tone, "this wouldn't be a problem if the two of you didn't receive so many detentions."

"Like you're one to talk, Moony," Sirius retorted, but he grinned at his friend. "How many did you receive last month?"

"Just one," Remus reminded him, speaking almost primly. "Compared to your...ten, was it?"

"Moony, it was ten between the two of us," James corrected, almost absentmindedly. He'd turned back to the table, and was muttering under his breath.

Not swears, or not ones that Harry knew. But it wasn't any magic that Harry knew, but he only heard bits of it.

The mirrors lit up, and James turned to his friends. "Try now!"

Sirius picked up one mirror. "Testing, testing."

Nothing happened.

"Say one of our names, perhaps? Or yours, first?" Remus suggested.

"Sirius Black speaking," Sirius answered, speaking directly into the mirror. "James Potter."

The second mirror flashed, and James grabbed at it so quickly, it nearly fell off the table.

"James Potter speaking. Sirius Black," he said, clearly.

Sirius's mirror flashed.

There was an eruption of cheers.

"It works! Bloody hell, Padfoot, it works!" cheered James.

The real Sirius chuckled. "Prongs was prone to swearing when he got excited. We knew it was big when he let loose a 'bloody hell.'"

Harry snickered, but kept his eyes on the scene.

"Now, why not try without saying the other person's name?" Remus suggested.

"Prongs, you go first," Sirius offered.

James nodded, then said, "James Potter."

Nothing.

"What about just the other person's name, and not yours?" asked Peter.

"Sirius Black," James said.

Nothing.

"Wait...I don't have mine with me." Sirius reached over and held up the second mirror. "James Potter."

James's mirror flashed.

"Sirius Black," James repeated.

Sirius's mirror flashed.

"Nice one, Wormtail. Here, you have a go," Sirius offered.

Wormtail held the mirror carefully. When James said his name, the mirror lit up. It also responded when the marauder said his.

"All right, then, they recognize the other speaker. That's great," said James, after the cheering had died down. "Next, we need to see how far the enchantments go."

"You mean, if they just work in this room? That's good, Prongs. Won't help in separate detentions if we need to be practically next to each other," Sirius acknowledged.

"Right you are. Let's start from the common room. It's not too crowded right now," James suggested.

"I'll head there," Sirius offered. "James, stay right here, all right?"

At James's nod, Sirius from the memory left the room, and James and the others fell out of sight as Harry and Sirius were forced to follow him.

"It's a bit like walkie talkies," Harry commented. "Have you ever used one?"

"No, but I've seen how they work." Sirius grinned. "Except ours aren't operated by battery and you can see each other's faces. A visual walkie talkie, perhaps."

Harry watched as the memory version of Sirius and James experimented over longer and longer distances. James even went as far as the outskirts of the Forbidden Forest before they had to call it quits for the time being.

The memory ended then, and Sirius gently pulled Harry from the Pensieve before the next one could begin.

"How'd you learn that there wasn't a limit over distance?" Harry asked, immediately. "Did you try to use them while on holiday?"

"Yes, but we had to make modifications over time. The mirrors initially worked only around the parameters of the Hogwarts castle. Which served our initial purpose for communicating while in detention, or in separate classes-" Harry snickered. "-but we discovered that once we left the castle, they could only be used at one wizarding location. All of Hogsmeade would work, as it was a village, and James's house was the same way, but we soon learned that we couldn't cross between two places. Not without a lot of effort and research for cross boundary enchantments. We managed by the end of our fourth year-that's the year you saw-but the memory you saw was around October."

Harry nodded. "And you were still figuring out how to became animagi at the time, right?"

"That's right. We knew we were close to a breakthrough by the end of our fourth year with that, and after a lot more research and experimenting over the summer, we managed it by the early fall of that year." Sirius made a face. "Snape nearly got himself killed just before the winter holidays, if I remember correctly."

Harry didn't particularly want to see that memory, but he imagined it wouldn't have been one Sirius had access to. It had been his father who had saved Snape's life, after all, not Sirius.

He felt a pang of annoyance at his former Potions teacher. Remus's closest friends had barely had the time to enjoy being with him in animal form, making the transformation that much easier, before Snape had nearly ruined everything for them.

Not that he wanted to dwell on this. "So, by the fifth year," Harry asked, wanting to have it all straight, "you had it so that the mirrors worked wherever you wanted, and you could turn into animals at will?"

"Yes, but we usually only transformed during a full moon. We felt it would be too risky to do so otherwise, and since Remus was-well, is-a werewolf, it's not as though he could transform with us when the moon was regular," Sirius explained.

"Could he have become an animagus, had he wanted?" Harry wondered.

Sirius shook his head. "He tried, using the process we did. All of our notes and everything. Didn't work. He figured that the werewolf inside him prevented him from being able to turn into another animal. There was another animal inside him, you see. And an animagus can only only turn into one animal throughout their life, and they can't pick which one. Really, it's a good thing that both your dad and I became fairly large animals. Could have turned out as mice or rabbits or something. We still could have kept Remus company in the Shrieking Shack, mind, but not have had any of the adventures we did."

"I'd love to see more of those," Harry said, with a grin.

"All in good time, pup, I promise." Sirius glanced at the Pensieve. "Ready for the last one for today?"

"Definitely!"

In they went, and the first thing Harry noticed was the four marauders examining a large piece of parchment around a table. He knew, immediately, that they were in the Room of Requirement.

All four of them were working silently, and then, Sirius stood up and stretched. "Blimey, my legs are killing me. Let's say we take a break from writing and see what we've got."

Peter was, of course, the first to agree, followed by James and Remus. Harry went closer to the parchment, only to see...

"Is this the Marauder's map?" he asked, turning to the real life Sirius, who beamed.

"Not the final version, but rather, a draft. We wanted to put every place we knew in writing, as accurate as possible, before doing the final version. Also," he added, gesturing to the large sheet, which Harry noticed was at least three times as big as his own map, "we had quite a big of resizing to do. This one was sized per scale, as a human one would be. In the final version, we made it so that each location took up the same amount of space, and the Resizing Charm put it so that the user could see a more accurate version as they were using it."

Harry looked carefully at the marauders, all stretching their limbs, but still very visible. "This was your seventh year, then?"

"Sixth. With the OWLs behind us, we were taking fewer classes, and had quite a bit more free time on our hands." Sirius gave Harry a gentle smile, as though reading his mind. "We'd also known that nonverbal spells would be a major component of our sixth year, so we'd started after our OWLs finished and into the summer."

"Which you could do without detection," Harry noted.

Sirius nodded. "Yes. Since all of us had at least one magical parent, we could practice without receiving any warnings. Even Peter had mastered the basics by the time we got back to school. Well, with a lot of our help," he added, smirking a bit. "Tutoring him did help us learn, though, because when you're explaining something to another student, it ensures that you really understand it, instead of just thinking that you do."

Harry nodded, then turned back to the others from the memory. Sirius had gone back to work, writing out "Room of Requirement" in his neat handwriting.

"That never shows up on the real map," Harry noted.

"That's because the founders made it Unplottable. Also, pup, it's hardly the only room that's like that." Sirius chuckled to himself. "It was rather more complex than we had expected it to be. Unplottable rooms, staircases that tend to move around, that sort of thing. We had to use spells to work our way around that. There were ways to work around this, but you had to ask for help-not just say the password to view the map," Sirius explained.

"What would you say to view the Room of Requirement, or other rooms like that?" Harry wondered.

"'Tell me all of the places that the map cannot show, and how to get there,'" Sirius quoted, using air quotes. "Of course, most students find out about the Room of Requirement on their own. House elves know all about it, and aren't bound by secrecy. The professors know, too."

"I first heard about it from Dumbledore," Harry recalled, keeping an eye on the marauders, even though they had resumed their writing and weren't writing anything Harry didn't already know from having lived in the castle for five terms. "He was telling someone at the Yule Ball, one of the other teachers, about how he had to go to the toilet one night and came across a room with loads of them."

Sirius snorted. "If that's the first time he entered the room, he's not as clever as we give him credit for. Still, makes for a funny story."

Remus wrote out the location of the living quarters for one of the professors who had since left, which was located beyond one of the empty classrooms on the fifth floor. There was no password for it, but Remus wrote that it involved a hand print. No way to get past that, Harry thought.

The Marauders continued their writing, occasionally glancing over at their neighbors before adding or crossing something out. Finally, James stood up, and stretched out the parchment so it covered the entire tables.

"Let's take a final look, shall we?" he suggested.

The others nodded, Sirius before Remus and Peter, and they stared down for awhile. Every so often, one of them would make changes, but by the end, everyone was silent, with smiles of varying degrees on their faces.

"Reckon it's time to start on the final version?" Sirius asked.

They might have, too, had Remus not tried to hide a yawn. Placing an arm around his shoulders, James grinned.

"Bit late, now. How 'bout tomorrow? Same time?"

There were varying nods, and then the scene vanished. Harry felt himself return to reality, the sitting room solidly before him.

As though expecting Harry to ask, Sirius said, "And you'll get the memory of us finishing up the final map tomorrow."

"Can't wait." A thought occurred to him as they rose. "Say, Sirius, why just one? Couldn't you make extra copies?"

Sirius chuckled, taking a seat on the charmed couch, and Harry followed him.

"Our plan was to make five maps in all. One copy for posterity, and four additional ones for each of us. Not that we needed it, but we figured we would pass ours along to our children if they showed any of our...adventurous spirit," Sirius began, chuckling. "It's partly my fault that we only had one."

"How's that?" Harry asked, stretching out on the couch, then wordlessly summoning the two blankets.

They wrapped them around each other as Sirius chuckled again, tucking them around Harry's feet, and then wrapping his arms around Harry.

"Well, we only wanted five copies ever to exist. Even with all the protective charms, we couldn't be too careful that it would get into the wrong hands," Sirius explained. At Harry's confused look, he added, "Not so much Death Eater aspirants, but, well, goody two shoes. Can you imagine if someone on Umbridge's squad got hold of one, especially if they managed to make the extra instructions read?"

Harry groaned. "That would have been awful."

"Exactly. So, we planned to make our copies and then place several strong anti-duplication charms on it. It was out of sheer stupidity that when we were adding the other charms to the maps, we forgot and added the anti-duplication ones as well." Sirius made a face. "We could have made another, but since we knew the castle so well, we reckoned we could tell our kids the secrets as well as the map. We sent the map off to the future, and haven't been disappointed."

"How'd you manage that?"

Sirius snickered. "You'll see tomorrow, pup."

Harry gave a good natured groan. "Oh, all right." After a moment's pause, he added, "Thanks for showing me these, Sirius."

Sirius chuckled and pulled Harry closer to him. "I'm happy to. It's one of the best parts of my day, pup."

"Same here," said Harry, breathing in the comforting scent of his godfather.

A/N: When you think about it, it was a bit odd that the Marauders only made one map, so I came up with the rationale here.

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