Disclaimer: I do not own Harry Potter. That honour belongs to JKR. Fred and George just wanted their own story told.

"My office boys, now!"

Fred's shoulders dropped slightly and he exchanged a look of defeat with his twin before the two followed Filch with a sigh. They hadn't even done anything that bad. Dungbombs stunk but they didn't cause harm.

George scowled as Filch led the two to his office. The cranky caretaker was smirking with undisguised glee at actually managing to catch the pair and he knew they would be in trouble now. Silently both twins prayed they wouldn't get a howler from their mother.

"Sit!" Filch snapped with a sneer. "Do not move!"

Fred sighed and sat in the chair in Filch's messy office. The room was overflowing with cleaning supplies, papers and dozens and dozens of confiscated items. Everything from itching powder to paint bombs.

The two gazed around the room, Filch muttering under his breath about hanging them by their thumbs (something he always threatened to trouble makers but wasn't allowed to do). Filch appeared to be searching for Floo Powder so he could notify Professor McGonagall without leaving them alone.

As the red headed twins waited George's eyes fell on a drawer which was partially open.

'Fred, look.'

Unknowing to anyone the two shared a mental bond which allowed them to speak telepathically. They hadn't told anyone about this ability, not even their parents, but had found it immensely useful during their few short months at Hogwarts, though both closed it during quizzes.

'What?'

'Look at that cabinet, in the drawer.'

Fred finally saw what George had been referring to and nodded subtly at his twin as Filch finally found the floo powder.

'I'll distract him, you grab it.' George told Fred via their bond. 'NOW!'

And with that George dropped the last dungbomb he had in his pockets, the resulting stench making everyone, including the twins, cough. Whilst Filch was trying not to gag and simultaneously shouting at the two boys and threatening them loudly, Fred stood up, made his way over to the cabinet and grabbed the ratty looking parchment from the drawer stupidly labelled 'Confiscated and Highly Dangerous'.

'Got it.' He told George.

The two fought grins as Filch flooed Professor McGonagall and she arrived in a shower of sparks, furious. It took her only fifteen minutes to clear the air in Filch's office and assign the two 11 year olds detention for a week. Then she dismissed them and left again, ignoring Filch's calls to have the two strung up in the dungeons.

Fred and George returned to their common room and broke down in peals of laughter. Filch's face had been worth the dungbomb stench and Professor McGonagall's charm had freshened them as well as his office.

"So what is it?" Fred asked his brother, George removing the parchment from his pocket.

George unfolded the parchment and the two frowned slightly. It was blank.

"I don't get it." George mused. "Why would Filch confiscate a blank piece of parchment?"

"Maybe it's written in invisible ink or something?" Fred suggested thoughtfully. "He wouldn't have taken it if he hadn't thought it was dangerous."

George's eyes gleamed. Many people felt Fred was the instigator of their pranks but in reality it was actually George who was the most mischievous of the two. The only thing was that his methods were a little more subtle than his twin's and the two encouraged the myth with their family and friends, Fred often playing the role of cover whilst George quietly set things up.

"Let's find out." George suggested. "The library would have stuff on revealing charms and potions."

"Alright but let's use the passage behind Jack the Giant Killer." Fred suggested. "We don't want to be caught in the library. Lee would never let us hear the end of it and Charlie would write to Mum!"

George laughed and nodded. "Alright, come on. I want to look up that charm for changing hair colour whilst we're there so we can use it on Filch."

Fred laughed as well and turned to get the parchment then stopped. "Hey, look!"

George walked back to where Fred was standing and gaped. Writing was appearing on the parchment.

"Password to Jack Giant Killer Passageway – mimbletonia"

"What the...? How did you get it to do that?" George asked in shock.

Fred shook his head. "I didn't do anything." He said softly. "The parchment did it on its own."

"On it's own?" George suddenly felt uneasy. "You don't think it's enchanted or anything do you?"

"Probably." Fred shrugged. "Why does it matter?"

George eyed the parchment warily. "Bill was talking about some of the books in the restricted section and he said that some of them are restricted because they try to suck you in to the pages." He told Fred. "What if this does the same thing?"

Fred shook his head with a half smile. "I doubt a ratty old parchment will do that." He scoffed. "It's probably just a key-word spell or something. Come on, we'll look it up." And he picked up the parchment and led the way to the library.

The twins spent several hours over the next few weeks looking for a way to figure out the map and its secrets. The more time that passed the more they were convinced that it had a purpose if only they could unlock it. It was a strange piece of parchment. It occasionally gave them passwords to passages and rooms and both were determined to get it to work.

However as the temptation of pranks and jokes began to take over and classwork built up the parchment became forgotten in Fred's trunk.

One day shortly after Christmas Fred couldn't sleep so he got out of bed and rummaged around in his trunk for a quill, ink and parchment and began making prank notes. Everyone else was asleep, even George was, and Fred sat quietly at 2am and began making notes.

First of all he listed all the pranks which already existed like dungbombs and itching powder. Then he began listing the charms he and George used.

It was a woefully short list and both he and George were both frustrated with the unimaginative jokes available.

'Fred, you awake?'

Fred jumped slightly as George spoke sleepily in his mind. 'Yeah, couldn't sleep.'

'What are you doing? You woke me up.' George mind asked, climbing out of bed. 'You aren't doing HOMEWORK are you?'

Fred shook his head as George slipped through the closed curtains and sat opposite him on his bed, the tiny lantern light the only light in the room. 'I couldn't sleep so I was looking at all the pranks we have.'

"Pranks? It's 2am!" George exclaimed.

"Shhhh." Fred hissed, George speaking out loud and causing Lee, in the next bed over, to stir slightly.

'Sorry.' George yawned. 'Give me a look.'

'It's such a short list.' Fred said in disgust. "You'd think people would have come up with better jokes than these by now." He muttered under his breath.

"Jokes and pranks are all very well but a true Marauder uses his brains."

George jumped as the list of pranks spells and products faded to be replaced by a message. "Fred!" He hissed.

Fred frowned and saw the writing on the parchment. "Oh, I must have grabbed the parchment from Filch's office." He whispered softly.

George shook his head in disgust. "What a waste of a week of detention." He muttered. "And with Snape too!"

"Maurauders unite against Severus Snape."

Fred chuckled. "Hey, I guess whoever made this didn't like him either."

George chuckled as well before sighing. "I just wish we'd been able to figure it out. I keep getting the feeling that it's full of cool secrets. I mean it told us the password for the passage behind the one eyed witch."

"That was awesome!" Fred grinned, remembering. The two had found a secret passage behind a statue of a one-eyed witch and discovered it led to Hogsmeade. There they'd covertly stocked up on their supplies of jokes without having to resort to mail orders or getting the older students to buy things for them.

"A test of minds and pranks open the world as seen by the Maurauders."

The twins stared at the parchment in confusion. "What IS this thing anyway?" George muttered.

"Why does it keep talking about the Maurauders anyway? It makes it sound like the name of a lame club or something."

"The Maurauders present ultimate aid of pranksters, tricksters and jokers."

Two red-haired 11 year olds glanced at each other. "Ultimate AID?" They asked together.

Both froze as two students shifted and murmured in their sleep, at the risk of being woken by the two astonished boys.

"What do you think it means?" George asked, the two much too confused and excited to focus enough for their mind-speech.

"Dunno. Maybe it's a spell directory or something." Fred suggested, his excitement rising anew.

"A serious vow of intent a Marauder in training must give, to unlock the secrets."

"A vow of intent?" Fred repeated. "What does that mean?"

George shrugged. "Maybe it's talking about a magical vow, that's taken with your wand. Bill told me."

"So maybe we have to swear something in order to get the map to open?" Fred suggested. "But a vow of what?"

The two frowned and sat quietly for a while, both thoughtful. Despite popular believe of their friends, family and teachers the two were by no means stupid. They were actually a whiz at potions and charms and often deliberately threw tests so they wouldn't attract the unwanted attentions of their teachers. Doing really well or really badly at something gave a person a lot of attention, something neither of them wanted as it stopped them from being able to covertly lay their harmless but funny traps. However now the two truly put their minds to work as they sat pondering the odd piece of parchment between them.

"Let's try some." George suggested softly and he took out his wand. "Um...I swear to keep the secrets of the Maurauders." He intoned, tapping the parchment. Nothing happened and the two frowned. "Ok, that didn't work."

Fred thought for a moment and then tapped the parchment with his own wand. "I swear to...um..." He thought for a moment and then grinned. "I solemnly swear to prank Professor Snape."

George stifled a laugh at this, trying to be quiet despite the mischievous look on his twin's face. "Nice." He grinned.

"Hey, look!" Fred gasped.

"Snape is a good start but Marauders do not limit themselves."

George frowned. "Ok." He mused thoughtfully. "Let's think this through. The parchment hates Snape."

"And it knows the passwords to the secret passages."

"And it asked us to swear a vow."

"But swearing to keep secrets didn't do anything."

"But vowing to prank Professor Snape did, though not enough."

Fred sighed. "This thing is stupid." He grumbled. "We could swear anything, how could we possibly know what the right thing to swear is."

"Hang on." George protested. "Look at the name. What is a Marauder anyway."

"It's someone who plunders." Fred replied. "They break the law..."

"They break the rules!" George interrupted, his eyes sparkling. "That's what these guys, whoever they are, must have done as students."

"Ok...so?"

"So that's how we have to think." George said excitedly. "We have to think like rule breakers. They don't want whatever this is to end up in the hands of someone like..."

"...like Percy." Fred nodded. "He'd never break the rules."

"Exactly!" George exclaimed. "So our vow has to show we're like them. That's why swearing to prank Professor Snape wasn't enough."

"We have to be willing to prank anyone, break the rules."

George nodded. "And look at what else it said." He grinned. "You had it right. It said we had to 'seriously vow'."

"What did I say?"

"You swore solemnly." George grinned. "Ok, let me try again."

Fred nodded, matching his brother's grin.

"We solemnly swear to break the rules."

"Wait." Fred said when nothing happened. "This isn't about what we'll do. It's about how we'll use the information this thing gives us. We have to swear how we'll use it."

George nodded. "And I'm thinking it needs to be us as a person."

Fred frowned. "Huh?"

"I think we have to say a vow personally. Vows don't work if they're made for someone else, you have to do it yourself."

Fred nodded, his excitement growing. "Ok." He grinned. "Let me try. I solemnly swear I'll...use this for mischief."

George grinned as lines began to appear and then sighed in frustration as they vanished again. "Darn it!"

"Close but not there yet."

Fred glared at it. "This is stupid!" He hissed. "This thing is too specific."

"No, it's not." George argued. "The makers obviously wanted to ensure it found it's way into the hands of people who would use it and not just turn it in like Percy would."

"But how can we find the right words?" Fred growled. He naturally had less patience than his brother and was getting frustrated once again.

"I'm not sure." George muttered. "Wait...let me think..."

"About what?"

"About the type of person these people wanted to use this." George mused. "It made me think of something."

"You said they wanted someone who would use it properly." Fred told him. "Why?"

George frowned. "The parchment asked for a vow of intent." He began. "And you were close before..."

"So?"

"So..." George mused. "They want to know we're like them. And we know Maurauders break the rules. They don't want someone like Percy to have their secrets so..."

"So maybe they want us to swear we're not like him."

George nodded, a grin creeping onto his face. "But we can't use his name, we need something more general, something he'd never say or do."

"Like...I solemnly swear I will not be a boring prat." Fred laughed.

"Or...I solemnly swear I am up to no good." George added with a chuckle. "Percy would never..."

Fred squeaked, cutting off his brother in shock. "George look!"

At George's words the parchment ink appeared again.

"Congratulations. You are now a Marauder in training. Messrs. Moony, Wormtail, Padfoot, and Prongs Purveyors of Aids to Magical Mischief-Makers salute you. To ensure the secrecy of the Maurauders MIT's against gits must hide their work and aids when they are done."

"MIT's?" George asked in confusion.

Fred laughed. "Marauders In Training." He laughed. "I like these guys but who are they?"

"Who knows, who cares!" George grinned. "Hey look, it's changing."

The two watched in awe as the ink faded and was slowly replaced by something else.

"Messrs. Moony, Wormtail, Padfoot, and Prongs

Purveyors of Aids to Magical Mischief-Makers

are proud to present

THE MARAUDER'S MAP"

"Marauders Map?" Fred repeated. "Come on George, open it!"

George folded back the flaps on the parchment and the two gaped at what they saw, their mouths dropping open in shock.

"Look it's..."

"A map..."

"Of Hogwarts!"

"Wait!" Fred exclaimed, his excitement growing. "Look...it's our dorm."

George peered at the parchment. "Is that...us?!" He asked in awe.

"And Lee." Fred pointed and then movement caught his eye. "Oh great Merlin! Look, it's FILCH!"

George looked as he watched a tiny drawn figure with a label above it reading 'Argus Filch' move down the corridor outside the Gryffindor common room. Beside it was another figure reading 'Mrs. Norris'.

"It shows animals?" George asked.

Fred gaped, unable to speak. "It shows people." He breathed in awe. "Do you really think it's right?"

George shrugged. "I don't know."

"Go into the hall!" Fred ordered in excitement. "If this figure labelled as you moves then we'll know it's right."

George nodded and got up, walking over to the dorm room door and into the hallway before returning again a moment later.

"It works!" Fred grinned in delight. "The figure that's you moved! It shows everyone."

For several minutes the two gazed at the incredible, wondrous, magical map in awe.

"Fred...do you have ANY idea what we could do with this?" George spoke finally, his voice filled with delight, excitement, mischief, wonder, admiration and more than a hint of reverence.

"We could plan pranks."

"Set them up."

"Explore the castle."

"Sneak into the Slytherin common room."

"Booby-trap the Slytherin common room."

"These Marauders...they are..."

"Gods!" Fred finished solemnly.

"My thoughts exactly." George agreed. "And probably why Mrs Norris is on here. I mean she catches as many students out of bed as Filch does."

Fred grinned. "Want to test it?"

George looked at him and nodded. "Let's go! There's no way I can sleep now."

The two hurriedly got out of bed and grabbed slippers and dressing gowns. Then they headed down to the deserted common room.

"Wait!" George stopped Fred. "We should work out how to reset this before we go anywhere. If we get caught we don't want people to be able to read it."

Fred looked at his twin with wide eyes and nodded. "It will be something similar to the activation phrase." He mused. "And probably short too for that exact reason."

George nodded. "Probably tap it again and say you're done with it."

"Finite." Fred tried. "Ok, apparently not."

"Mmm...something like how they'd say it." George suggested. "Rules broken?"

Fred shook his head. "How about linking it to the other wording." He said. "We solemnly swore we were up to no good, how can we say that shorter?"

"No good isn't just pranking." George agreed. "And these are the wonderful Marauders we're talking about."

"Hey, remember what it says on the front?" Fred pointed out. "Look...'purveyors of Aids to Magical Mischief-Makers. Mischief." He tapped the parchment. "Mischief done."

"Mischief finished."

"Mischief managed!"

At Fred's words the ink began to disappear and George slapped him on the back in glee. "Brilliant Fred!"

Once the ink was gone Fred grinned. "My turn. I solemnly swear I am up to no good."

The two grinned in delight as the map reappeared again.

"Alright, let's test this."

"And put a dungbomb in the potions lab." George smirked.

Fred laughed and the two examined the map, looking for people around the entrance to the common room. The hall was empty so they snuck out and made their way down to the potions lab. The map even showed the ghosts and the two spotted Peeves approaching, ducking into an empty classroom to avoid the naughty poltergeist and fighting delighted laughter as the map proved its usefulness.

Within 20 minutes the two had planted the dungbomb in the potion's lab and wound their way back up to their dorm. Both were tired now. It was 4am and despite wishing they could stay up and explore the castle they were both yawning and they knew they had to get some sleep before their first period Transfiguration class with Professor McGonagall. Sadly the two returned to their common room, George taking his first turn at wiping the map blank again and storing it under his mattress for safe keeping.

'The castle is ours now Georgie.' Fred told him with a happy sigh as they got back into bed.

'And it's all thanks to the Marauders.'

A/N: If you find errors please let me know. I've tried to find them all but have probably missed some typos somewhere.