Title           : working title – Hogwarts under siege

Author       : odyssey

Disclaimer : This story is based on characters and situations created and owned by J.K. Rowling, various publishers including but not limited to Bloomsbury books, Scholastic Books and Raincoast Books, and Warner Brothers Inc. No money is being made and no copyright or trademark infringement is intended.

Spoilers    : to be safe – for all four books

Summary  : When a mysterious disease attacks Hogwarts in Harry´s 7th year it is up to Prof. Snape and his band of merry Slytherins to find a cure in time.

Dedication : To all the great fanfic-writers whose stories have brought me hours of pleasant entertainment. I hope that I can give some of it back with my little narration.

Preliminary comments : Thanks for bearing with me through the last chapter. As a reward we finally get closer to finding a cure. Enjoy : )

~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~

   It was well past midnight when Harry and Draco returned from their `discreet investigation´. After the laughter of the numerous teachers had subsided and the blush on Harry and Draco´s faces had faded it was decided that the students had a right to know what was going on since this is what Dumbledore himself would have wanted. In fact, Prof. Sprout had even been very touched and understanding when Draco had told them a sad story about the terrified seventh-years of their houses which had not had a single peaceful minute since Moira´s breakdown each fearing to fall victim to the disease the very next second. So Harry and Draco had decided out of a feeling of responsibility to find out as much as they could about the `emerald disease´ in order to soothe their classmates´ fears. In the end – as a concession to the special danger which the seventh-years were in – Harry and Draco had been allowed to stay for the rest of the conference provided they kept quiet. Finally, after hours of talking and arguing the assembly ended and the boys shuffled back to Gryffindor tower where they woke up a grumpy pink lady in her frame.

   `Pork chops.´ Harry murmured and the pink lady swung open with a heavy sigh.

   `Running around in the middle of the night! Hmpf!´ she complained after the boys climbed through the portrait hole but they didn´t pay her any attention.

   Harry stretched lazily trying to work the cramps out of his muscles which had been inactive for too long. `That´s quite some story you told them, Draco. You almost convinced me, too.´

   The silver-haired boy faced his companion with a frown. `It wasn´t just a story, Potter. Look around you, people are terrified! And they have a reason to – especially our classmates.´

   `Are you terrified?´ Harry raised a dark eyebrow while Draco seemed to be lost in thought.

   `Yes,´ he finally replied in a low voice, `Only a fool wouldn´t be afraid of this disease. You have seen what it does.´

   Harry didn´t respond but deep inside he had to admit that he was also afraid. What would happen if Ron or Hermione were infected? Or Ginny? Potter shuddered involuntarily.

   `Harry?´ Ron´s voice interrupted the silence. `What took you so long?´

   The redhead emerged silently from his dorm followed by several more seventh-years from both Gryffindor and Slytherin.

   `Yes,´ the small voice of Neville Longbottom cut in, `What did you find out?´

   `Quite a lot actually. Someone should wake up the girls.´ Harry replied as he let himself fall into his favourite plush chair by the fire.

   `There is no need to do that.´ Pansy Parkinson came out from her hiding spot behind the door which led into the girl´s dorm and gave Draco a nonchalant smile while whistling once, sharply, but quiet enough not to wake anyone. A short moment later several naked feet could be heard as they made their way down the steep staircase and within seconds all the chairs in the common-room were filled by anxious Gryffindors and Slytherins and the tables had been filled with supplies that eager `helpers´ had brought from the kitchen.

   `So, boys, was your little tour successful?´ Pansy tossed her golden curls out of her face. 

   `Sure,´ Harry replied with a confident smile ignoring Draco´s ironic snort at his answer.  

   `Everything went very smoothly.´

   Malfoy nearly chocked on his butterbeer. `If that´s your definition of smooth…hmpf!´ he mumbled darkly but didn´t make any further comments as Harry reported everything – or rather nearly everything – that had been said. In the end they had had to admit being caught by the teachers but that went by almost unnoticed next to the startling news that the seventh-years had to digest.

   `…basically that means that Snape and the two guys, they belong to the Ministry for Magical Maladies and Injuries by the way, will continue their research. Snape seemed determined to work through the night in order to isolate the virus from Dumbledore´s blood sample…´

   `Is it clear that we´re dealing with a virus?´ Hermione interrupted in an impatient voice.

   `What else could it be?´ Draco answered with a sneer. `It´s a disease, so it has to be induced by a virus.´

   The headgirl shot him an contemptuous look. `It could also be caused by a bacteria or toxins or even prions. There are dozens of possibilities.´

   `Pri-what?´ Malfoy shot Harry a questioning look saying *how does she know all this?* but Harry only made a helpless gesture. He was already used to Hermione´s bottomless amount of knowledge and had given up any attempts at challenging her in that department a long time ago. Still, seeing Draco stare at her with a mixture of anger and wonder on his face made Harry smile as he resumed his speech.

   `Anyway, Snape will try to isolate this whatever-it-may-be this night. This could prove to be a great starting point for finding a cure. Next to that Draco and I made a deal with Prof. McGonagall:  Gryffindor and Slytherins seventh-years get full access to everything concerning the disease but we have to keep it to ourselves in order to prevent a panic.´ Here Harry shot a pointed look at the Slytherins which returned it with icy glares.

   `You have our word.´ Blaise stepped forward and Harry mumbled quietly under his breath. `Great, the word of a Slytherin. That counts a lot.´

   Furiously Blaise made a grab for Potter but was distracted by Ron who lunged for him. Crabbe and Goyle marched forward to protect Zabini while Dean Thomas and Seamus Finnigan advanced simultaneously in order to help Ron.

   `Stop that you idiots!´ Draco hissed sharply and indeed, Crabbe and Goyle who were used to obeying him ceased immediately while Harry struggled to hold the Gryffindors in check.

   `Let´s make a deal between ourselves.´ Malfoy suggested, `Potter will be held responsible for anything that leaks out by the Gryffs while I will take full responsibility for the Slytherins, o.k.? Do I have your word, people?´ he asked the Slytherins who nodded grimly. `That´s good enough for me. Potter?´

   `Hm...o.k., Gryffindors can keep secrets so there´s no need to worry.´ Harry ran his hands through his already untidy hair leaving it in more of a mess than before. `Let´s continue, then. In addition to secrecy concerning all `inside information´ it´s going to be our task to find out as much as we can about the circumstances of the infection. That means we´ll have to research everything from Moira´s last meal to Bert´s socks to rumours about Fawkes etc. I suggest that we all take some time to write down everything they recall about the potions lesson where Moira collapsed. Next to that it could be of importance to reconstruct the days before her collapse. Every detail could mean a break-through! After we´ve finished our reports they will be collected and handed to Snape, Abbot and Cuther, that´s the specialists.´

   `You know, I could go through the report before that.´ Hermione mused. `It would save them some time if the reports were already searched for patterns or suspicious things…´

   Blaise Zabini nodded thoughtfully. `Sounds like a good plan to me. They will be too occupied to waste their time on this. Draco and I can help you with that, don´t we D?´

   Malfoy shrugged in a bored way. `Sure. Why not?´

   Harry nodded contently, finally some kind of cooperation took place. It had taken a plague to bring them all together but apparently it worked, he thought completely oblivious to the brawl which had almost taken place a few minutes ago. `Good.´ Potter smiled, `Let´s do these reports and while you analyse them the rest of us will question the other students and find out as much as we can. Our headquarters will be the Gryffindor common-room, this is where we will bring all our reports. Operation `kick the plague´ has begun!´ Harry declared in a mockingly-serious voice and the Slytherins rolled their eyes. Some of them, however, smiled at Harry´s joke.

   Although the students had decided to go to sleep and start their work tomorrow anxiety held most of them awake until it was almost dawn. They were eager to start doing something instead of sitting around and waiting to fall ill. The steady scratch of quills against parchment was only interrupted by whispered conversations in the deep of the night discussing the identity of the attacker. For surely someone must have set that disease free. Had Draco told the truth when he had said that the Death Eaters were innocent? Or maybe it had been a crazy fanatic? Or an over-enthusiastic ministry agent? Or someone else? And why didn´t Snape fall ill?

   Finally the last quills fell out of tired hands and deep silence filled the room as the last of its occupants glided into sleep.

*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~

   Flickering light danced over Severus´ face bringing out its hard lines and drawing odd shadows over it. He was too tired to stifle a yawn and stretched himself in his hard chair. A few inches behind him Abbot was working on the samples of the ominous green substance carefully labelling each phial and attaching a list which bore the indigents it contained. So far nothing important had been found but both men were determined to continue till they found something or dropped down from exhaustion. At the moment the latter was more likely.

   `Uuuugh!´ Abbot stretched unceremoniously far away from looking like the noble ministry specialist that he was. `Severus, I´m going to get some more tea from the kitchen. Would you like me to fetch you some coffee?´

   `Hmm?´ Snape raised his head slightly from Dumbledore´s blood sample. `Coffee? Oh yes, with some extra caffeine, please. Thanks Phaedrus.´

   Oddly enough Severus got along quite well with Phaedrus Abbot. The two men shared their own brand of black humour and a love for strong drinks: one preferred strong black tea while the other worshipped coffee. Severus was quite impressed with the progresses Abbot had made by analysing his samples. He had found a way to determine who was infected and who was not and at the moment prepared several testing devices which would be used the next day to examine every person in the castle. Next to that Snape and Phaedrus also shared a growing antipathy towards Mr. Algernon Cuther who was snoring peacefully on a couch in the back of their laboratory after Severus had slipped some sleeping potion into his tea (`Green peach tea with just a hint of sugar and a healthy amount of milk, please!´).

   Shaking his head in an attempt to clear it Severus returned to his work. He picked up the phial which he had prepared and positioned his wand carefully.

   `Centrifugio!´ The phial began to rotate, slowly at first but increasing its speed with each turn. The blood which it contained began to divide itself into its various contents, the heaviest of them were pressed together at the bottom of the vial while the light ones accumulated themselves near the opening. After a while Severus decided that the phial had rotated long enough, finished the incantation and slowly opened the phial (not without renewing his protection spells of course, one could never be careful enough!). Snape bit his lips in concentration as he dipped a long needle into the red mass at the very bottom of the phial and put a sample of them into a small glass container.

   `Identificio!´ he mumbled while dropping a small amount of his identification potion for proteins on it. Severus waited. And waited. And waited a little more. Then the potion made a hissing noise and some steam appeared while the sample changed its colour from red to a bright blue. A-hA! That was good! He thought with grim satisfaction. He was getting nearer to his goal of isolating the virus, only fifty more potions and he´d have it! Perhaps, if he was lucky…

   Severus rubbed his tired eyes, reached for the next potion and let a few drops fall onto the sample while crying `Identificio

~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~

   `You already finished your report?´ Ron asked with raised eyebrows while Lavender nodded sagely.

   `Sure. Spent the whole night writing it because I put in everything I remembered. Actually, I had no idea I remembered that much.´

   `Oh, great, I guess.´ Ron turned around to face on of his classmates who was just leaving the common-room. `Megan! Where are you going?´

   The blonde stopped and smiled at him making his ears turn red in embarrassment. `I´m going up to the owlery.´ she informed him in a sweet voice while Ron tried to wipe away the stupid grin which had plastered itself upon his face. `You know, Ludwig´s been very depressed since Moira´s collapse.´

   Ron frowned. Ludwig?

   Megan must have understood his silent question as she laughed lightly. `Ludwig is Moira´s new owl. He´s really beautiful, a very seldom mountain owl. I´ve been looking after him ever since…you know.´ 

   `Of course,´ Ron nodded thinking feverishly about anything that might sound impressing to her. `Um…Well, what´s he like? Ludwig, I mean. Is he a nice owl?´

   She smiled up at him. `Yes, he has become quite attached to her. Much more so than he was in the beginning. He´s a little rude with people he doesn´t know and Moira´s had some problems with him in the beginning. She just managed to get his trust as…´ Megan bit her bottom lips to keep it from trembling and blinked rapidly. `I have to go now. See you, Ron.´

   She hurried off  to the owlery leaving Ron at the mercy of Parvati and Lavender. Ron winced.

~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~

   The day had passed without Severus noticing it. Breakfast had taken place without him and so had lunch. Apparently the had been brought a new can of coffee at some point but he had been too absorbed to acknowledge anything beside the virus.

   `Yes!´ his caffeine-soaked brain suddenly yelled as he saw the face of his enemy for the first time. It was small, formed a perfect ball and sprouted several long mean-looking spikes. `Got you!´ Severus cried triumphantly calling Abbot´s attention.

   `Severus? What is it?´ the lean man ran over from his samples which littered the whole table.

   `That´s him! I´ve isolated him!´ Snape tipped the glass which held the probe with his wand and shouted `Projecto

   Light accumulated over the container and formed a shivering form: the virus.

   Severus and Phaedrus shared a genuine smile. They knew how it looked! That gave them dozens of possibilities to fight it!

   `We could use a variation of the disarming charms to rid it of the spikes. Then we-´ Abbot suggested excitedly but was interrupted as the picture wavered. The virus seemed to move his spikes and started shaking until only a red blur could be made out and then, after a final violent tremble it stopped and the two startled men looked were faced with a new problem. The virus had changed its form.

   `Damn.´ Phaedrus hissed. `I hadn´t anticipated that.´

Comments :

· Fairygirl : Thank you for your kind words! As for the ideas that other people have thought of first: I know that feeling. But if you´re interested in writing a story that deals with the same topic feel free to do so! I´d certainly R/R it : )

· Demeter : I´m so glad that you liked the Harry and Draco part since it´s my favourite from the last chapter. In fact, Harry and Draco are such complete opposites that you get the feeling they have to be together and annoy each other. Let´s face it: if Mrs. Rowling would ever decide to make Gryffindors and Slytherins cooperate in order to get rid of Voldemort he wouldn´t stand a chance! Thank you for your review : )

· Star magic : Thanks for the review! Oh, by the way, how would you have reacted if Harry and Draco came toppling out of an Invisibility cloak in the middle of a conference? It was either laugh at them or toast them! They practically owe Prof. Flitwick their lives. I have the distinct feeling that he won´t have any troubles with a certain Slytherin for a while.

· Elspeth : Interesting ideas…you´ll have to understand that I can´t answer them without giving everything away but you already drew at least one correct conclusion : )  I´m trying to keep up the tension and mystery but judging by the speed that you deduct my clues you´ll have a cure in a maximum of the next two chapters. Well, I guess after reading this chapter you know how Moira got infected and probably have an idea about Bert´s infection, too. It will be confirmed in the next chapter. Until then I thank you for your review and wish you a happy search! P.S. The ministry of Magical Maladies and Injuries asks if you want to have a job? You get your own office, fireplace plus floo-powder and a sponsored broomstick! And on a personal note: pleeeeeaaaaaase update `Not all scars are visible´! I just LOVE your version of Sirius…and Severus…and Remus…and….you get the idea.

· PurpleSailorSaturn7 : Thanks for the reviews as well as telling Narcissa about the story. Biiiig hug! I hope that you enjoy Snape in this chapter since he hasn´t gotten as much attention as he deserved in the last one. Anyway, I hereby declare that I dedicate the `virus-isolation´ sequence (where in addition to `Softy-Snape´ and `Sarcastic-Snape´ a new facet of his personality is shown: `Intelligence-Snape´) to my fellow Snape-admirer, PurpleSailorSaturn7!

· May : I´m glad that you liked that previous chapters and very grateful for your reviews! Of course I agree with you, a Gryffindor / Slytherin-combination is unbeatable! I LOVE stories where Draco and Harry have to team up but still hate each other to the bone. They´re too amusing! About the clues: I´ve hidden them under a lot of unimportant rubble. I know that´s evil but you won´t have to wait for long and all will be revealed : )

· Polgara : Thanks for the review : ) Of course you can ask for more chapters and I´ll even deliver! According to the rough plan that I have made there will be 10 chapters in total and an epilogue which I´ll try to upload with the last chapter. Bear with me, please! 

· Anneliese : Thank you for your nice review. It always warms my fuzzy little heart to get kind reviews : ) Like I already mentioned I adore the Harry/Draco-combination as well. I wrote Flitwick´s reaction by imagining what I would do in such a situation. Imagining Draco´s and Harry´s faces has helped as well. I sure wish I had a photo of that moment : )