The common room was immersed in a cloud of acidic smelling smoke. Frightened students were piling up the staircases, waving hands and books in front of their faces or hiding their mouths under any piece of fabric they could find. Lily fought her way through the frantic thong, a sleeve pressed firmly over her mouth and her wand held stretched out in front of her. A desperate sixth year slammed into her on the last few steps and pushed past with a barely muttered apology, but Lily dived between two skittish third years and emerged coughing underneath an upturned sofa near the fireplace. She crawled out cautiously, still clutching her wand, and stood up. After a moment in which she adjusted her robes and dusted herself down, Lily found that her stinging eyes had begun to make some sense of the gloom around her.

The fire had gone out, but the smoke that curled around the room had a greenish and slightly sparkly quality. It smelt odd too. Not far away Jocelyn emerged from the now deserted stairway and hurried over to her, a fresh cotton handkerchief plastered over most of her hand. Pressing her sleeve tighter over her mouth, Lily held her wand further aloft.

"Lumos," she muttered. The command did very little, but through the slight increase in light a squinting Lily thought she could make out some figures among the thicket of the smoke in the centre of the room. Wordlessly, she grabbed her friend's hand and proceeded forwards, her wand still held cautiously before her.

"Nice one, Wormy. Now do you think you could open a window?" a slightly muffled voice demanded from its position in an armchair.

"Yeah, okay, sure, I can do that," Something large crawled out from a table beside Lily's legs. She trot rather viciously on it's fingers.

"Yeeauch!"

"Can somebody tell me what on earth is going on here?" Lily demanded, striding forwards and poking her wand right in the middle of the figure on the armchair.

It turned out to be a rather bemused Sirius Black, reclined nonchalantly in a somewhat diagonal position with his feet resting on a few cushions stacked on the floor. He was tall, well-built, if a little gangly and had a rather effeminate nose and cheekbones. His black hair, Lily remembered because she certainly couldn't see that much of it, was half-long, in as far as it fell into his eyes and covered his ears, and usually very sleek and shiny, although riddled with split ends.

He batted the wand away with a grin and sat up. "Why sorry Evans… it is Evans, right?" he mused sardonically. "Good old Peter here," He waved a hand loosely to where a small round pastry-faced boy with a thin mess of very pale brown hair sat sucking his hand and staring reproachfully at Lily. Jocelyn reached down as if to help him with it, but he snatched his hand away, blew a raspberry at the very surprised girl and scampered back under the table. Sirius grunted a laugh at this as he continued, "Accidently let off this bag of Filibuster's exploding spark bombs. Unfortunately they're intended strictly for use in wide open spaces, so the effects were rather interesting. We didn't disturb you, did we?" He paused and raised his eyebrows at her in apparent concern.

Lily responded by jamming her wand straight into the bridge of his nose, forcing him to fall back against the armchair in alarm. "Didn't disturb me?" she repeated incredulously, her voice somewhat hoarse from the smoke, "Didn't disturb me? You've successfully smoked out the common room, trashed half the furniture and created a bang loud enough to have rocked most of Gryffindor Tower – and you're wondering whether or not you disturbed me?"

"That would be it, yes," Sirius replied, carefully sliding his thumb and forefinger onto Lily's wand so that he pluck it out of his face for the second time. "I would hate to think we had interrupted your important…" he paused, his brow slightly furrowed in thought, "Whatever it is you girls get up to up there."

Lily could feel herself shaking with rage."You mean little…"

"Now, now, Evans," came a voice behind her and a hand caught her rising wand-arm and pulled it away from Sirius, "You know, it really isn't very nice to threaten people like this. I'm surprised at you."

As Jocelyn screamed, it only took Lily a moment to spin on her heel and catch her assailant a stinging slap across the cheek. A rather stunned James Potter, also somewhat tall but skinny with unruly black hair and thick wire-framed glasses, drew back, his hand tentatively touching a red mark just below his eye.

"Careful Evans," he snapped, "That hurt!"

"Well maybe next time you'll know that I don't just threaten then," Lily breathed angrily, tossing a few stray stands of ginger hair from her face. "Now then, lets see," she fingered her wand threateningly as she drew back. To her surprise, the smoke cleared around her. From the corner of her eye she noticed that her fellow fifth year Prefect, Remus Lupin had successfully opened a window and cast a spell to draw the smoke outside.

"Twenty points from Gryffindor for all three of you for the disruption you've caused and an extra ten, for all three, for the possession of banned fireworks," she recited, drawing herself upright and extinguishing her wand as she replaced it inside her robes, "And when I come back this evening I had better find Gryffindor Tower returned to the condition it was before your exploits today or I shall see all three of you in detention, understood?"

"Yes, McGonagall," Sirius muttered sourly, sitting up.

"What was that, Black?" Lily snarled, turning around to face him.

"Yes, Miss Evans," he repeated in slightly louder voice, standing up and making rather a mocking show of fluffing out some cushions, "Whatever you command." Jocelyn scowled at him, her arms folded. James looked as if he had eaten something that didn't agree with him.

"By this evening," Lily repeated cooly, "And Josey, see to it that they don't make anyone else clean up instead. Now if you don't mind, I think I should like to get on with the rest of my birthday – unless you've got plans to ruin anymore of it." She stalked forward and slammed the portrait hole behind her as she left.

Peter crawled out from under his table and blew a raspberry at the closed painting. Jocelyn glared at him.

"So that was Evans," James mused thoughtfully.

"Yep," Sirius snapped, flopping back down into his chair, "Lily Evans, perfect Prefect and prissy cow extrordinaire. Buzz off, Harkiss…" He waved his hand irritably towards where Jocelyn was puffing herself up in an attempt to assert her friend's authority.