It was a warm summer day in March, in the year 1975, and four Gryffindor fifth-years lay sprawled carelessly on the grass next to the lake. One of them, a handsome boy with messy dark hair sat up at the sight of a red headed girl walking past , her nose pointed in the air, studiously ignoring the four. Another of the boys, also extremely good looking with long black hair poked the first boy in the side and looking at the girl, yelled. "Oi, Evans!"

Lily Evans looked back at them and her lip curled. "Hello Sirius. Evidently you haven't learned much about the merits of good company.", she said, staring at the first boy who was gaping at her like his every dream stood right in front, before walking off. A third boy, scrawny and mousy haired, snickered at this and the fourth, who had been silent all this while, quietly smiled.

Sirius Black laughed as well, seeing his messy haired friend avert his gaze and turn red. "Well James, I doubt that could have gone any worse. The one good thing is that she isn't hanging around with that greasy Snivellus anymore." James Potter looked at the ground and muttered something that his mother would most certainly ground him for if she had heard. Sirius went on. "You're fine winking at a hundred other girls after a Quidditch match, but one look at Evans, and you act like a Full Body-Bind Curse has been cast on you. Or do something irrevocably stupid. What do you think, Wormtail?"

The scrawny boy grinned and his whole face brightened at being included in the conversation. Peter Pettigrew spoke up: "James, that girl is never going to give you the time of the day. Heaven knows there are enough girls in our year, not to mention other Houses, who are absolutely crazy about you. Why do you insist on making a fool out of yourself? Tell him, Moony."

Remus Lupin, who had been quiet all this time, merely patted his friend on his back. "Now, now, James still has two more years to convince her that he isn't a waste of space. Not that I'm optimistic, but there's always hope. Right, James?"

James grinned at his friends, though his skin was still tinged with a slight blush. "Right. Now, moving on... Remember last month's excursion?" Sirius laughed again. "How could I forget? Filch almost caught us as we were coming back into the castle. Poor Wormtail almost had a fit."

Seeing Peter open his mouth to protest, James quickly went on. "Well, upon further reflection, what if we could make sure that we knew where everyone in the castle was at any given time? Say, if we enchanted a map of Hogwarts, showing all the passages, even the secret ones, to show the location of all the castle's inhabitants? How could we go about doing that?"

Lupin frowned slightly. "We could use a Homonculous Charm I suppose. That would let us track the movements of every person in the mapped area, through labelled dots that move around. Its supposed to be a horribly complicated spell though."

Sirius snorted. " Please. We managed to become unregistered Animagi without any help. This should be a piece of cake. Speaking of cake, I'm hungry. Let's sneak into the kitchen again, and discuss this further over some pastries."

The four friends made their way towards the kitchens, bickering and planning how to make their idea work. And thus, the notion of the Marauder's Map came into existence.