Disclaimer: I'm not J K Rowling, and I don't own Harry Potter or any related charcters/settings

Rating: T for violence/adult themes

Summary: MWPP fic set in their second year. James gets a very useful Christmas present, and three Marauders try to solve a mystery

-------------------------------------------------------------------------------------------------------

Most of the Gryffindors had returned from the holidays, and with the common room full Remus and Sirius had retreated to their dormitory. They were playing Exploding Snap when the door was burst open by another small explosion; in the form of James Potter.

"Hi there," he said as he slung his belongings in a heap on the bed. Peter followed through the door in James' wake. "Good Christmas?" He did not wait for an answer. "I got the best present ever from my dad... you'll never guess!" He threw himself onto the remaining space on his bed and grinned at them expectantly.

"Year's supply of Fizzing Whizbees?" suggested Sirius. "Snap!"

"Wrong!"

"Ouch!" Remus felt the end of his nose gingerly; he had been painfully close to the exploding cards. "Um... Prototype Nimbus 1500?" Remus would not have been so pleased with that as a present, but to James' Quidditch-obsessed mind it probably would seem like the best present in the world. Not that there was any chance of him getting one; the prototypes that had been produced and released in a fanfare of publicity last autumn had all gone for trials with international teams.

"Better," replied James gleefully. His eyes were sparkling in a way that suggested mischief was brewing.

"Better than a Nimbus 1500?" echoed Sirius doubtfully, looking up from his self-appointed task of exploding the rest of the pack of cards. Peter was gaping at James in awe. Remus turned his chair round to face James, aware that with this much build up they were not going to be told his secret until he was satisfied he had their complete attention.

"No more guesses?"

All three of them shook their heads.

"Ok, wait there." He sat up and dived into his trunk, sending a small shower of socks in Sirius' direction. Sirius pushed them back onto James' bed with a small noise of disgust, and when he looked up again, James was nowhere to be seen.

"Where'd he go? James?" Remus' mouth had dropped open and his eyes were as wide as Peter's. Neither of them seemed to be able to answer Sirius; the best Remus managed was to point at the bed and stutter slightly.

James laughed and suddenly his head reappeared, floating a few feet above the bed. The sight gave Sirius such a shock that he fell out of his chair.

"Blimey! That isn't..."

"That is!" James reappeared in stages as he disentangled himself from a long, silvery cloak. As soon is it was off, Sirius pounced on it and held it up to the light. With a cry of delight, he swung it around his shoulders and he too vanished from sight.

"An Invisibility Cloak!" crowed Sirius' disembodied voice. "You have the best dad!"

"He told me not to get in any trouble with it," laughed James as Sirius pulled off the Cloak and handed it back. "I don't know what else he expects me to do, giving me that! Shall we try it out tonight?"

Even Remus only made one or two half-hearted protests.

Lessons started next morning, and all four of them got into trouble in their first lesson, Herbology, for inattention. They had been up all night, roaming the corridors under cover of James' Cloak. They had found two new secret passageways; terrified a pair of choirgirl ghosts witless and followed Argus Filch around on one of his patrols, stifling peals of laughter whenever he turned around and peered straight through them. The price for this hilarity was that they were now close to dropping asleep at their bench.

By the time they had retreated to the common room for the evening, they barely managed to stay awake long enough to make a hashed attempt at some homework before crawling up to bed, and they were fast asleep within seconds.

That did not discourage James one bit. Next morning at breakfast he and Sirius were already planning their next escapade. Somehow they had obtained the password to the Slytherins' common room, and with an Invisibility Cloak the opportunities were limitless.

"Tonight?" suggested Sirius when their plans were complete.

Remus – who did not look as if he had fully recovered from their last night of wandering – blushed. "Um... I can't, tonight."

"Ah, Loopy! You can't chicken out on us. We need you there; you're the only one who's really mastered that Charm."

"Go on, Loopy. It'll be fun."

"No, I can't. I'm... I'm visiting my mum again this evening."

"Oh. Well, ok. We'll put it off 'til you get back then." No more was said; they all felt sorry for Remus, with his mother so ill.

They used the evening to catch up on homework instead, as much as Sirius complained it was a waste of his time. They took it in terms to try and explain things to Peter, wondering how Remus managed to be so patient with him.

"No, Peter," said Sirius, exasperated. "Like this." He waved his wand and beaker of water in front of them started bubbling. Professor Flitwick said they would be heating and cooling harder things than water soon, but Peter had not even mastered this.

"You do it too fast," whined Peter. "I don't get that flick at the end..."

"Just try, will you?" Sirius turned the water back to normal and Peter, an expression of apprehensive concentration on his face, did his best to copy. The surface of the water shivered for a minute, then one big bubble formed, burst, and the beaker cracked, yet again. The water drained out and one of the halves of the beaker rolled onto the floor. With a deep breath, Sirius bent to retrieve it.

"Hey, Sirius," Sirius banged his head on the underside of the table as he tried to look up at James, and yelped. He emerged a second later, rubbing his head and glaring. James was looking out of a window onto the grounds, frowning. "Didn't Loopy say he was going to visit his mum again today?"

"Yeah, why?"

"Isn't that him there, walking across the grounds?"

Sirius scrambled from his seat with another sigh, and joined James by the window. Peter looked up from the battered and struggling textbook and watched them. "Where?" He followed James' gaze. "Actually, you're right. That does look like him. With Madam Philpot, isn't it? I wonder what... Why would he have said he was visiting his mother if he wasn't?"

"I don't know... hang on, I'll get my Cloak."

Neither Sirius nor Peter questioned why; this was a mystery demanding to be solved, exactly what James' new Invisibility Cloak needed. They could, of course, wait until they saw Remus the next day and ask him to explain it, but that thought never occurred to any of them.

All four of them had fit under the Cloak on its first expedition, so three should have no problem, but they still had to walk slowly to avoid a foot slipping out and giving them away. By the time they reached the grounds, there was no sight of their friend or the Matron.

"Dammit," muttered Sirius. "Which way were they heading?"

"We need to move round so we can see the common room window. We can have a better guess from there." Neither Sirius nor Peter had a better suggestion, so still moving carefully they headed towards the foot of Gryffindor Tower. Knowing that a member of staff was wandering this part of the grounds, they did not dare light a wand to show them the way, but the moon shone brightly on the snow, and between it and the lighted windows of the castle they could see well enough.

"Well, here's the Tower," said Peter unnecessarily when they reached its base. "Where did you see them?"

"Over this way a bit," replied James, pointing and pulling both his friends with him. He glanced back at the common room window to get his bearings and then stopped near the greenhouses, peering around as if he expected Remus to jump out from behind one of them.

"I can't see anything..."

"Shh!" A lantern light had just appeared in the distance. They edged warily towards it to find Madam Philpot returning. Alone. They stood carefully to one side, out of her way and held their breath as she passed within inches of them, muttering some spell under her breath. They waited for her lantern to be once more out of sight and then shed the Cloak.

"Where is he?" They walked further along the route Madam Philpot had taken but found no sign of Remus. Their three sets of footprints trailed behind them but there was no sign of any belonging to Remus or Madam Philpot. They were so occupied looking for their friend that they paid very little attention to their surroundings until Sirius was knocked off his feet with a startled yell and they realised that they had wandered into the shadow of the Whomping Willow.

James narrowly avoided another branch as he backed out of the tree's reach, and though Peter was hit, he too scrambled clear with no damage.

"Vicious bloody thing," muttered Sirius angrily as James helped him to his feet and Peter retrieved his wand, which had gone flying when he had. "I'll get it one day," he added, brushing snow from his clothes and blood from his forehead. Most of the boys in the school played a game of trying to get close enough to touch the Willow's trunk. Peter declined to join in, knowing he would never manage, but James and Sirius were both fairly accomplished, getting nearer than many. Oddly enough, when they had convinced him to have a go, Remus had proved to be one of the best in the school, dodging the flailing branches and getting within a hands-breadth before being beaten back. He had laughed off the bruises and cuts that resulted but no amount of persuasion had made him try again.

"This is pointless," said Peter.

"He's right," admitted James reluctantly. "We can't search the whole grounds for him, and we've no idea where he went."

"We'll have to keep a close watch on him next time he says he's visiting his mum," said Sirius. "With the Cloak it shouldn't be too difficult."