Chapter Six: Severus Snoop

The next day the school was buzzing with rumours about what had happened to Mary and, though some of them were accurate enough, it was soon spreading around that Mary had had her eyes gouged out, that she had been permanently transfigured into a Japanese monkey ('they're called "Macaques",' third year Callum Brown told Alice Law very solemnly), and that she had actually been killed and her body was being kept in the Hospital Wing until her parents could come and collect it.

In truth, Mary was still up in the Hospital wing, heavily sedated with Calming Draughts, and hidden behind a set of curtains, while Madam Pomfrey and two St. Mungo's healers, who specialised in curse damage, worked on her to reverse the spell. Professor Carnarvon had also been called to the Infirmary, in her capacity as a curse breaker, and was working on the theory of undoing Mulciber's grisly work while the qualified healers dealt with the practical side of things.

This meant Defence Against the Dark Arts was cancelled for a few days, and - though the boys were very sorry about what had happened to Mary - they were very glad of the extra hours off where they could get on with more homework.

Lily, Mandy and Petra stayed at Mary's side every moment they were allowed. Mary became quite adept at understanding messages traced into her palm and always seemed much comforted by their presence. As the days passed, and the healers worked tirelessly on her, she began to see flashes of light, and hear a strange ringing in her ears and Madam Pomfrey told the others, with some satisfaction, that progress was being made and Mary should be as good as new within the week.

Meanwhile, it was widely reported that Mulciber and Avery's parents had been brought up to the castle, the very same evening Mary had been attacked, and had a meeting with Dumbledore. Mulciber and Avery had not been seen since. ('They've been expelled,' Connie Bidwell of Hufflepuff told Sandra Lewis of Ravenclaw. 'Filch has them clapped in leg irons in the dungeons,' Callum Brown told anyone who would listen, 'because you can't just go around turning people into monkeys'.)

In fact, they had been sent home for a week, in disgrace, and then would be under house arrest in the Slytherin common room for a month, not even allowed to attend mainstream lessons, but being watched over by whichever member of staff happened to be free. It was Slughorn's personal duty to make sure they did not speak to any of their housemates during their confinement.

'Why not just chuck them out?' James asked, in frustration, when this particular titbit of information finally reached his ears (he struggled to hide his disappointment that Callum was not right, though it had seemed far-fetched and too good to hope for.) 'Or better yet, chuck them in Azkaban?'

'I don't think Dumbledore ever expels if he can avoid it,' Sirius said. 'Remember what he said when I fed Reg to the manticore after it turned out Reg had been attacking everyone? He didn't want either of us cast out, where we would fall under the influence of Voldemort. He'd rather keep Mulciber here and try and rehabilitate him than kick him out and leave him with no option but to join the Death Eaters.'

'But Mulciber is practically a Death Eater already!'

'Yeah, well, that's Dumbledore for you. He believes in redemption… Sees the best in everyone.'

'It's a bit suspicious that Mulciber used that curse on Mary, don't you think? The one Professor Carnarvon told us about?'

Sirius frowned. 'What? You think she told us all about it on purpose, hoping someone would be foul enough to actually use it?'

'We still don't know what she was doing at the Slytherin common room, and she was at The Leaky Cauldron the night it was attacked. And now this… All I'm saying is suspicious events are building around her and I remain…. well, suspicious .'

But Professor Carnarvon is helping them cure Mary, you plonker.'

It was James' turn to frown. 'Well, she would have to - wouldn't she? If Dumbledore said, and she doesn't want to blow her cover. Doesn't mean she's not happy Mary got attacked.'

…

Meanwhile, as the rest of the castle were busy wildly speculating about Mary, Severus was off trying to solve a mystery of his own. Ever since Black had made that remark about the Whomping Willow, Sev had been agonising over the meaning of it. He sat in his dorm, chewing on his fingernails, and ruminating on his words. He sat in lessons and felt his eyes inexorably drawn to the window, looking out at where the willow stood quiet and unassuming at the edge of the forest.

It was true enough that he had seen for himself Madam Pomfrey lead Lupin over towards it, every full moon, and that she returned alone and then went back to get him in the morning. It was true they headed to that tree and then Lupin vanished, but Severus could not quite parse out Black's meaning in telling him to "prod the knot" and so his nails were bitten to the quick as he turned the riddle over in his mind.

The Whomping Willow was dangerous, everyone knew that. They were forbidden to go near it after Davey Gudgeon had nearly lost an eye way back in the mists of first year. Severus himself had been knocked out by it and faced expulsion shortly afterwards due to the idiocy of Potter and Black. And now Black was telling him to go back to that tree.

Was he just hoping Severus would get hit in the face by a branch? Get his block knocked off? It was crude and childish, if so, but then Black was crude and childish, and so that was exactly the sort of dimwitted plan Sev would expect him to concoct.

Or perhaps his reach was greater than that? Anyone who went near the tree would be expelled. That was what they said after Gudgeon got hurt. And Severus had already broken that rule once and survived. Perhaps he could not another time. Perhaps Professor McGonagall - overlooking the fact that she had not expelled her precious Gryffndors for the exact same thing - would see to it that a Slytherin was expelled for going near the tree, especially the same one twice. Perhaps Black was hoping Severus would take him at his word, start examining the tree and get kicked out of school for breaking the rules.

That would make Black and Potter very happy indeed, and Severus did not want to give them the satisfaction.

But then perhaps… perhaps Black was telling the truth, and there was a knot in the base of the tree, and this was somehow linked to where Lupin was disappearing to every month ( "to transform " he added in his mind, but then quickly pretended he hadn't because he did not want to get his hopes up and had to remember that this was probably all some cruel trick on the part of Black to make Severus look ridiculous).

And if that knot was there … well … then what? What would he discover if he prodded this knot (if it even existed) with a stick, as Black had advised? (It crossed his mind that the knot itself was a trap, and that by prodding it the willow would explode, or hurl projectile tree branches or do something else deathly dangerous in order to protect itself from attack. It crossed his mind that Black's intention was to have him murdered by this tree… and that Lupin was simply disappearing into the forest to transform. There had always been rumours about werewolves living out in the forest…)

After a couple of days, sitting and staring at the Whomping Willow out of the window was no longer enough and he made the decision that he would get a little closer, take a closer look, though he was still very wary of it all being some giant prank to make him look a fool - and so he endeavoured to make sure he went unnoticed by Black and his cronies during his investigations.

He crept outside at Wednesday breaktime. He had just had Charms with the Gryffindors and, after making sure that the four loathsome toads had headed off in the opposite direction, he sneaked down the marble staircase and out of the great, oak front doors. It was blustery now; the leaves were turning red and gold and starting to fall and the sun - though bright - held no warmth, while the wind carried with it the promise of a winter yet to come. Severus wished he had brought his cloak, but he did not want to catch the attention of his fellow Slytherins by returning to the common room.

It was easy enough to leave the castle without anyone missing him. With Mulciber and Avery at home in disgrace, and Lily forever sitting beside the sickbed of the McDonald mudblood, he was spending much of his free time alone at the moment and, though he could always join Rosier and Wilkes, or Regulus and his friends, if he did not wish to be alone - none of them would notice he was missing if he disappeared off by himself.

On exiting the castle, he turned and scurried behind the greenhouses, wanting to remain hidden from anyone who might be looking out of a window, and then dashed as fast as he could down the lawn and just beyond the treeline of the Forbidden Forest. He then wended his way along the forest edge (keeping a weather eye out for centaurs or any other monsters that might attack him - that would give Black no end of satisfaction too) until he made his way back to where the Whomping Willow stood.

It seemed like any other tree at the moment, its leaves rustling in the breeze. Standing behind it, and from this distance, Severus could see no sign of the supposed knot he had been told to prod. So, after stiffening his spine and squaring his shoulders (and preparing for a tree branch to smack him right in the kisser) he scuttled forward. But once he was within eight paces, and still unable to see the knot, the Willow seemed to sense his presence.

It came alive. Its branches began to swing, as if searching him out, raining hard blows down on the earth. One bough came right at him, scything straight at his feet, and he had to jump it, like a muggle jumping a skipping rope back in the playground in Cokeworth. The branches smashed down harder, the tree itself began to creak and groan and shake, as if it was trying to uproot itself to get at him… And, after a while, feeling disappointed, Severus backed away.

He could not reach the knot from the back (if it even existed, if Black's entire plan had not simply been to have Sev decapitated by an angry tree branch) and so - with regret - he gave up and headed back to the castle.

This was not the end of it though, he swore to himself. He would try again and again, until he had circled the entire willow, scanned every inch of the base of its trunk for this so-called knot. And if it was there… if it was there… Then. Well, then he would decide what to do once he had that information. Whatever Black intended for him was unknown, and he had no intention of playing straight into his loathsome hands… but he was not going to ignore what might be his best lead so far in getting rid of that cowardly, pathetic excuse of a prefect, Lupin.

If Lupin was a wolf (and Severus knew he was) then Severus would get him. And it would all be Black's fault.

…

The rest of the week passed by uneventfully enough. Mary was improving but still not able to leave the Hospital Wing, and if anybody noticed that the weird Snape boy kept nipping outside during free time and circling one particular tree, no one said anything about it. Certainly, his behaviour did not draw the attention of the four Gryffindor boys, who remained - as ever - drowning in a sea of homework from which they had little chance to look up.

When Saturday finally arrived, they did allow themselves to take a slight breather. James had Quidditch practice that afternoon and - while he was upstairs getting ready - the others sat in front of the fire and enjoyed a well earned break. Peter was working away at his comic (about a young werewolf boy named "Moony" who acted as a spy for the muggle Queen of England) and was practising the most ornate, looping cursive handwriting he could manage for the Queen's speech bubbles (Moony's own speech bubbles were written in what looked suspiciously like Remus's handwriting).

The real Moony was busy not spying for Her Majesty's Secret Service, and was in fact busy reading a book about the Tokoloshe - mischievous, dwarf like water spirits which could become invisible, and which haunted magical communities in Africa - including the wizarding school, Uagadou.

And Sirius had an alarm clock and his wand, and was carefully (and with great enthusiasm) taking the clock apart, examining the springs and coils to see what they did, and then putting them back together.

'What are you going to enchant that to do?' Remus asked him, peering at him over the top of his book.

'To run away and hide when it goes off - so its owner has to get up and find it. And then, I'm going to swap it with James' alarm clock. Don't tell him.'

Remus grinned. 'Wouldn't dream of it.'

'Pete.'

'My lips are sealed!'

'Well they'd better be - or I'll seal them with the curse of the Three Wise Monkeys.'

Before Pete could retort, there was a noise on the stair and James appeared, wearing his Quidditch robes and carrying his broomstick over his shoulder. 'Think fast,' he threw Remus's camera at him, Remus's hands shot out and caught it deftly before his brain had even worked out what it was.

'Nice reaction times - we should play you as seeker instead of Regulus Bowel Movements.'

'Oh yeah - and no one would mind me missing matches because I was in the Hospital Wing after a full moon.'

'Oh… yeah. Anyway - you couldn't play without replacing me - and I'm too brilliant. Come on, the lot of you, and watch me practise - get some fresh air. Moony, I want you to take photographs so I can see how I look.'

'You are dangerously vain, Mr. Potter.' But he smiled, and got to his feet and - along with the others - followed James out of the common room, down the stairs and all the way out to the Quidditch pitch, where James joined the rest of the team and they took seats in the stadium.

Once again, there were many spectators sitting on the benches - almost as excited to watch the practice as they would be to watch a real game. Lily and Mandy were there to support Petra, and Regulus's best friend, Tristram Rowle, was sitting high up with some other fourth year Slytherins and Severus (Mulciber and Avery were now back in school but in total confinement, so Sev was having to hang around students from other years when he was not sneaking off alone), Angus MacDougal's friends were there (Ellis Stebbins among them - much to Sirius's disgust) and there was a huge contingent of Hufflepuffs cheering on the Jones siblings.

The whistle blew, the brooms rose up in the air, and the team were off, playing a mini game - the chasers passing the quaffle back and forth as they took shots on goal, Gwenog and Emrys trying to keep the bludgers from unseating them and Regulus soaring above the rest of them, keeping an eye out for the snitch.

Up in the stands, Sirius leaned back, closed his eyes and wished he had brought his alarm clock to tinker with. He could hear the whirring and clicking of Remus's camera beside him, as the other boy took pictures of James' moves.

By the hoops, MacDougal launched himself from his broom, gripping it one handed, and spread himself out like a starfish to block a goal. There was an appreciative whoop from his friends in the crowd when the quaffle bounced off his chest (and an appreciative whoop from Peter, when it then rebounded off Regulus's head. Sirius opened his eyes, 'What did I miss?')

A moment later, a bludger hurtled at James and he only avoided it by a wand's width, rolling beneath his broom using the sloth grip technique, and then righting himself once the danger was passed. Peter whooped again. 'Did you get that, Remus? Did you get that on camera?'

'I got it.'

Things looked like they were really coming together. The team was making great strides in working as a cohesive unit; the chasers were tight and seemed to work so well together it was as if they were reading each other's minds; MacDougal took a lot of risks, his goalkeeping style was bold, but it always seemed to pay off, and the Jones siblings were like a pair of human bludgers themselves, thundering around and sending the heavy balls hurtling away from their teammates with great resounding cracks as their bats made contact with them.

'Reg is the weak link,' Sirius said, watching his brother circle the far end of the pitch, while the snitch glittered near MacDougal's ankles.

'Your being harsh on him, because he's your brother and you hate him,' Remus said mildly. 'He's perfectly adequate.'

'Adequate? Even I've spotted the snitch and I've literally just opened my eyes! He's hopeless… Oh, there he goes.'

Regulus had finally seen what everyone in the stands had noticed (and which Tristram had been yelling at him about for five minutes) and was flying towards MacDougal's goalposts, his face flushed - though with embarrassment or exertion only he knew.

What happened next happened so fast no one was quite sure how it did happen or whose fault it was, but one moment Reg was flying for the snitch, head down against the wind, while James, closing in on the goal, passed the quaffle to Petra so she could take the shot and then: Smash! James and Reg had collided mid air, banging into each other so hard that they both fell off their brooms and tumbled through the air, the hard ground rushing up to meet them.

High in the air, the players came to a stop, in the stands everyone jumped to their feet and watched in agonised terror as the two boys plummeted to earth. Peter had flung his arms over his head to shield his eyes, Sirius was swearing copiously and Remus was vaguely aware of a girl screaming somewhere behind him - a long drawn out wail which seemed to echo as he watched James tumble to the ground in what seemed like slow motion, buffeted by the wind and toppling as if he was doing somersaults. The camera fell from Remus's hand but he did not register it.

The moment seemed to last forever, and be over all at once. There was one second where Remus was sure James was going to die, and the eternity in which he watched it happen… And then the two boys hit the pitch… and bounced. There was the boinging sound of springs, and the pair of them were thrown back up into the air by a few feet, and then landed again, and bounced again, each bounce smaller and gentler, until they came to a stop, looking slightly shell shocked but otherwise unharmed.

Still swearing, Sirius started to run, jumping down the stadium benches three at a time and then over the barrier to the pitch as if it was a hurdle, not even breaking stride. After a moment to realise all was fine, Remus and Peter ran after him, huffing and puffing and scrabbling their own way over the barrier with far less elegance than Sirius had managed, even in his anguish. The springy surface of the pitch made it hard for Sirius to run but he stumbled and staggered his way to the fallen boys and then, shoving Regulus out of the way, threw his arms around James. 'You absolute wanker!'

'Gerroff! I'm fine.'

'I thought you were dead.'

'You're messing up my hair!'

'It's always a mess. You total git. Don't you dare do that again!'

Remus and Peter arrived, tripping over their feet as the surface of the pitch continued to bounce beneath them, and fell on top of the pair of them. 'You absolute idiot!'

'James, are you alright?'

'He's fine - the total berk - but he won't be if scares me like that again.'

Looking rather sour, Regulus struggled to his feet, and turned to find Tristram Rowle making his way towards him much more sedately. 'Bad luck, Reg.'

'It was Potter's fault.'

The other spectators were invading the pitch by now, and the team had landed, and there was much confusion and cacophony and exclamations and explanations (and a fair bit of falling over, and yet more shrieking), and James and Reg had to repeatedly tell all and sundry they were fine - while Moran and MacDougal flew off to collect the boys' brooms, which had drifted away to the other end of the stadium.

…

Sitting alone now, on the highest bench, Severus put his wand away. It was a shame to have to save Potter's life, in order to save Regulus's - but Regulus was a pureblood and a good contact for Sev to have, if he ever hoped to join the Dark Lord. His own muggle last name would never get him into the inner circle, he would need friends to vouch for him, and there were not many higher born than Black. It would not do to have him die needlessly before he had been of any use. Besides, it was not as if Potter would ever know what he had done… and, on balance, Severus would rather see the loathsome toad expelled than dead.

If Potter had died in the fall, it would have been too quick, his suffering over before it had begun. And Severus planned to make Potter suffer before he was done with him.

As he sat alone and unnoticed, the only person not on the pitch, his sharp eyes caught sight of something lying where Lupin had been standing. He got up and - totally unobserved, as the entire crowd was still swarming around Regulus and Potter - he made his way down through the seats until he reached what he was looking at.

He picked it up and began to smirk. Thinking this could come in very handy for Lupin's own downfall, he pocketed it, and then left the stadium.

…

It was not until a couple of hours later that Remus realised he had misplaced his camera. 'I had it earlier,' he said, rummaging around in his belongings in desperation. 'Where can it be?'

'Maybe you left it at the Quidditch pitch?' Peter suggested.

Remus's eyes lit up. 'Yes - I don't remember having it after James fell, come on!' and, though it was dark, and rain was starting to fall in large, cold drops which trickled down their necks, he dragged the others back out to the stadium in order to search.

'Lumos!' They lit their wands and began to sweep around under the benches near where the boys had been sitting, and - when they found nothing - took their search higher and higher until they were at the very tops of the stands, where they were forced to conclude: 'It's not here!'

'Well, maybe someone found it and handed it in to Madam Hooch,' Sirius said comfortingly, when he saw the despondent look on Remus's face. 'You can check with her tomorrow. Come on - it's freezing, we're getting wet, and it's nearly time for tea.'

So they headed back to the Great Hall and helped themselves to stew and dumplings, and apple crumble for pudding. Remus still looked glum. 'I hope I find it,' he said. 'That camera was my mum's… I'd hate to lose anything of hers.'

'You will,' Sirius gave his hand a comforting squeeze (though he spoke through a mouthful of dumpling) and then - looking at the teacher's table - asked. 'Who's that man with Dumbledore?' He nodded his head towards a man of about forty, in smart robes but with greying hair.

'That's Jacob Scrabble,' James told him. 'Head of the Department for Magical Games and Sports. He must be here to discuss the tournament.'

…

Across the Gryffindor table, Petra was giving the same information to Lily and Mandy. 'He's having drinks with Professor Slughorn later, I've been asked to go along and fill them in on how the team is progressing.'

'Oh that should be good. "Everything's fine and we probably would win, except Potter and Black are massive arses and can't get along",' Lily said.

Mandy shuddered. 'It was still horrible watching them fall from the sky though.'

'Not as horrible as me sitting in a dungeon with Slughorn and some Ministry Bigwig, drinking oak matured mead together, is going to be. I'm no good at schmoozing! It's just going to be awkward. I can't think about it without cringing.'

'Well, let's think about more pleasant things… Like how we're going to get back at Mulciber,' Lily said. Mulciber and Avery were locked away in the Slytherin dungeon, as they spoke, but it would only be a matter of a time before they were out and about, as if nothing had happened.

The girls were angry and frustrated that the two of them had cursed Mary so horribly, could have left her to die a slow and agonising death, and yet got away with it so relatively easily. 'They should be in Azkaban!' was a constant refrain up in their dorm (though they avoided talking about it when they were with Mary, in case any mention of Julian Mulciber upset her - her hearing was starting to come back and they did not want her catching only snippets of their conversations, which might cause her even more distress).

They planned to seek their own revenge, to make up for the lacklustre punishment Dumbledore had doled out, but had yet to come up with anything they deemed nasty enough. 'At least we don't have to worry about getting expelled, though,' Lily had said pragmatically. 'If Mulciber got away with what he did. After all, we won't try to kill him.'

'No, we'll let him live forever with the pain,' was Petra's dark response.

But, so far, they had had no joy in finding a curse that was just as awful as Mulciber deserved, but which stayed just on the right side of Dark Magic (though they had been tempted by one they found in an old spell book which would give him "razor filled testicles upon his chin" and another which would turn him inside out) and so Lily and Mandy agreed they would head up to the library for another look through the books, before they went to visit Mary, while poor Petra was doomed to spend an evening making awkward Quidditch chit chat with the grownups.

…

To celebrate James surviving falling from his broomstick, to calm Sirius's nerves after watching James nearly die, and in order to cheer Remus up after losing his mum's camera, it was decided that the four of them would sneak out of school and into Hogsmeade for an evening of butterbeers and bar snacks at The Three Broomsticks. They crept out of their dorm and made their way to the statue of the one eyed witch, followed the passageway to Honeydukes and then fled from the sweet shop and out into the street, without being noticed.

It was still raining as they made their way towards the pub, large, steady drops which splashed coldly against their skin, and they turned the collars of their cloaks up, put their heads down and hurried along as fast as they could. The roaring fire came as a great relief when they finally sat down in front of it.

James and Sirius went to buy the drinks (Peter was a little annoyed about this; he had been looking forward to seeing Madam Rosmerta and knew full well that Sirius would not appreciate the opportunity to flirt with her like he would have). They returned a few moments later clutching four butterbeers, a packet of pork scratchings and some peanuts - which they spread out on the table for everyone to share.

'She laughed at my joke,' James told Remus and Peter. 'It was a good one too. "What do you call a chameleon that can't change colour?" ,'

'A reptile dysfunction,' Peter and Remus both intoned (James had told this one often).

'Yeah - well, she hadn't heard it. And it made her laugh.'

'More importantly,' Sirius said, taking a seat and stretching his legs out towards the fire so the flames toasted his toes, 'we need to be careful. Professor Carnarvon is over in the corner. We don't want to get caught out of bounds.'

Remus and Peter craned their necks to peer across at where a flash of bright sequins and some steel grey eyes told them that their Defence Professor was, indeed, in The Three Broomsticks that evening. She was sitting at a round table, nursing a gillywater and chatting to a goblin.

'She shouldn't even be here,' James said resentfully. 'I heard her talking while we were at the bar. She has some Hufflepuffs in detention tonight - but she left them writing lines in her office, with Filch watching over them, and snuck away to the pub to meet one of her Gringotts mates. Honestly, where do teachers get off coming to our pub when we just want a quiet, relaxing, illegal night away from them?'

'Does she have no shame?' Remus asked dryly.

She doesn't,' James replied, matter of fact. Remus flicked a peanut at him. James lobbed a handful of pork scratchings back.

'Sshhh!' Peter squealed. 'Don't get too rowdy, or she'll notice us!'

They finished up their first round of butterbeers and headed to get seconds (James took Peter with him to the bar this time, as Peter was showing signs of sulking if he got left behind again, and Sirius was quite comfy toasting his toes).

'You're still worrying about your camera,' Sirius said to Remus, once they were alone. It was a statement, not a question.

'Yes. I don't know how I could be so careless… I don't know what my dad will say…'

'He won't say anything, because he never needs to know. We'll get it back.'

'If someone took it….'

'Then it has to be one of the people who was at the stadium with us. If Madam Hooch hasn't got it, then we'll work our way through the list and torture a confession out of someone.'

Remus smiled wryly. ' I don't remember everyone who was there. You had your eyes closed half the time…'

But Sirius only shrugged. 'Pete'll remember. He notices everything, and he has to have some uses…'

James and Peter returned from the bar, full of the tales of how Rosmerta had winked at them ('and that must mean something,' James said earnestly), and by the time they had finished their second butterbeers, Professor Carnarvon had got to her feet and left the pub, her goblin friend at her side. She had not glanced in their direction once, and they assumed they remained undetected.

'So now we can relax,' James said. 'At least until Hagrid gets here. Madam Rosmerta says he usually gets in a bit later… Unless he goes to the Hogs Head instead.'

'Maybe we should try the Hogs Head one day,' Sirius suggested. 'I heard it's a bit seedier than here. They might give us something a bit stronger than butterbeer.'

'But then we wouldn't see Madam Rosmerta!' Pete protested. 'Not that you would care.' Sirius threw a handful of peanuts at him. Peter threw some right back and - no longer wary of being caught by a nearby professor - the four of them descended into peanut throwing, pork scratching lobbing and even firing the occasional hex.

A few butterbeers later (and after Rosmerta threatening to kick them out for their wild behaviour) the boys heaved themselves up from their chairs, fastened on their cloaks and staggered out into the street, where it was now raining very heavily, indeed, and the wind was blowing it in almost horizontal sheets straight into their faces.

'This is miserable!' James shouted over the wind and rain. 'What were we thinking coming out on a night like this?'

'We were thinking you were a stupid git who almost died and I needed to recover from that!'

'You can't kill me! I'm invincible!'

Trying to keep their faces turned away from the worst of the winds, they battled their way down the street back towards Honeydukes, where they discovered a serious blow to their plans: the shop was in darkness and had been all locked up for the night.

'Maybe we could use Alohomora ,' James said, pulling out his wand, but Remus reached out a hand and stopped him.

'They almost certainly have some kind of intruder alarm charm on the shop. We'll get caught.'

'So now what?'

With nothing else for it, and grumbling a great deal, they abandoned the main street of Hogsmeade and walked further out, past the Shrieking Shack (Remus shuddered and did not look) and up into the mountains, where they knew that - if they followed a certain path - they would find a crack in the cliff face which opened up into another secret passageway leading back to school.

It was rough going though, the path was uneven, with loose stones to slide on and tufts of grass to trip over and it was so pitch black that - though the four of them all lit their wands - they gave barely any more light than the pinpricks of stars billions of miles away.

Still, with grit and determination, and a serious desire to get out of the driving rain, they managed to stumble their way up the mountainside and eventually reached the cave.

It was a relief to be out of the elements, but the dark inside was suffocating and, trying not to think that this must be what life was like for Mary right now, they kept one hand on the rough walls to help guide them back down the passageway to the castle.

This was a longer tunnel than the one that led directly to the heart of the Hogsmeade; it twisted and turned and - in the blackness - even seemed to double back on itself. Eventually, they reached what appeared to be a dead end, and knew they had come to the back of the fourth floor mirror which was the school-side entranceway to the passage.

'Pete, you go first.'

'Why me?'

'You're the sneakiest. And Moony can't risk getting caught, can he? He's a prefect.'

Scowling, Peter eased open the mirror and peered around, only to squeak and pull it shut as someone hurtled past in the corridor outside.

'What?' the others asked him.

'The coast wasn't clear.' He pressed an ear to the mirror's frame and strained to listen. 'There's more people… lots of footsteps. Running.'

Remus frowned and held his lit wand above his left wrist so he could look at his watch. 'Everyone should be in their common rooms by now - it's past eleven.'

'Well - they're not… There, I think that's the last of them.' He pushed the mirror open again, peeked, and then jumped down. 'It's clear.'

They all followed him, and had only just closed the mirror back up, when there were more rushing footsteps and Callum Brown rounded the corner. 'Have you seen?' He asked. His face was flushed and he seemed to be in a state of high excitement. 'What happened? What was the explosion? Where was it?'

'Explosion?' Sirius frowned.

But Peter kicked him, before Callum noticed anything. 'Everyone's run that way,' he pointed down the corridor, 'we were just going.'

'Well, come on, then!' and - noticing nothing amiss - Callum scurried off in the direction Peter had pointed, and - not wanting to look suspicious or miss out on the fun - the four of them followed him.

'Don't kick me again,' Sirius muttered under his breath to Peter, sounding rather threatening.

Peter flushed. 'Well don't say anything stupid then.'

The further they went, the more people they found, all streaming upward, and the higher they went - the thicker the air seemed to become, a faint smell of smoke became stronger and stronger and then, as they neared the Defence Against the Dark Arts Classroom they found themselves pushing their way through a choking haze of black fog.

'It was Professor Carnarvon's office,' Callum told them, as they joined the throng of people milling around. 'I think it's blown up.'

'Was she in there?' James asked. But Remus thought it unlikely - she had, after all, just been at the pub with them. For a moment, though, he thought he was wrong - as Madam Pomfrey suddenly appeared through the smoke, leaving the office with a stretcher floating by her side…

But a quick glance told Remus it was not the professor who was injured. Filch lay on the stretcher, covered in a blanket and unconscious, dark smudges and burn marks all over his pasty face - which was all that was visible of him.

Another figure emerged from the gloom, and after a moment materialised into Dumbledore. 'Argus took the worst of it,' Madam Pomfrey was telling him. 'But the students should go to the Infirmary as well.'

'The detention,' James whispered. 'With the Hufflepuffs… She was having Filch watch over them. He must've kept them late and then…' He trailed off and waved a hand to encompass the smoke blackened corridor and the door, which bore scorch marks and was half blasted off its hinges.

'Keket,' Dumbledore said, turning to Professor Carnarvon, who exited the office after him, looking rather shocked and pale beneath the brightness of her headscarf, 'we will fix things up in the morning, I think - for the time being - it might be best if you, too, spend the night in the Infirmary. Whatever has happened here, we do not want a repeat of it or to put you in any unnecessary danger.'

He then looked at the crowd of students, peering through the thick smoke to try and see what was going on. 'I'm sorry you have all been disturbed,' he said to them, 'and as you can see - something unfortunate has happened here tonight which I will have to get to the bottom of. However, Mr. Filch and the students will be fine, there is no real harm done, and so I must ask you all to return to your dormitories… now .'

Understanding that the Headmaster was in fact not asking, but telling, the crowd began to disperse, though they chattered excitedly among themselves - discussing what they had seen, how their ears had not stopped ringing since the blast, and wondering who could be behind it.

'Well, Carnarvon must have done it, mustn't she?' James said, once the four of them were safely back up in their own dorm at the top of Gryffindor Tower.

'But she was at the pub with us,' Remus pointed out, 'she couldn't possibly have -'

'What if she did it remotely? Or - or set a curse on a timer? I bet she knows how to do that, she worked for Gringotts as a cursebreaker, she must know all sorts.'

'But why would she want to blow up Filch?'

Sirius snorted. 'Who wouldn't want to blow up Filch? I'm with her there.'

'I just think it's more likely someone wanted to blow her up, and got Filch instead. Who would have known she was planning to go to the pub and wouldn't be in her office?'

'She would,' James said triumphantly, as if he had proved a point. 'She got herself safely out of the way and then Kaboom! '

'And she wants to blow up her own office because…?' Remus asked sceptically.

But James was exasperated. 'Because she's evil!'

'She was at The Leaky Cauldron that night you were, Remus,' Peter pointed out. 'This isn't the first attack that has happened around her. She could have - have led the raid on The Leaky Cauldron, for whatever reason the Death Eaters were there - let them in once the pub was closed, and then she's blown up her own office to throw Dumbledore off the scent.'

'The scent of what?'

'Whatever she's planning to do!' the three of them all yelled at Remus in unison.

'Look, Remus, we know she's up to something,' James said, 'because we saw her down by the Slytherin common room getting up to something.'

'Dark Magic,' Sirius added.

'It's certainly a possibility. And Dumbledore - well - he's a genius. If she's up to something, he will figure it out sooner or later. But by blowing up her office, she makes herself look like a victim, throws suspicion elsewhere, only she does it on a night when she's safely out of the way so she doesn't actually get hurt.'

'Or she was the intended victim, and whoever blew up her office didn't know she was going to the pub,' Remus stated. 'It's just a matter of deciding which is more likely.'

'And I think it's more likely that she's a Death Eater,' James said - and would not be swayed in his opinion, sticking to it stubbornly as they changed into their pajamas and switched the light out.

…

The next day was Sunday, and the school was still rocked after the sudden explosion of the night before. Lily and Mandy went up to the Hospital Wing to spend time with Mary and explain as best they could to her, through writing on her palms and yelling over the ringing in her ears, why the Infirmary was now so full. Petra held a Quidditch practice - but the team seemed dazed, and only flew through the motions, before calling it quits after an hour. And all over the castle, little huddles of people would meet up in hidden corners and whisper among themselves about what had happened, what they had been doing when it happened and - most importantly - why they thought it had happened.

The curse (for that is what it turned out to have been) had exploded inside Professor Carnarvon's desk. Filch, who had been in the office, supervising the detention, had been prowling around near the window - threatening to whip the Hufflepuffs to within an inch of their lives when they breathed too loudly - and had taken the brunt of the blast, but had been far enough away to not be seriously injured. Had Professor Carnarvon been there, had she been seated at her desk - as surely she would have been - she would have been blasted into smithereens.

It seemed that only James and the others thought there was a chance Professor Carnarvon was the one behind it all ('But then we know more than everyone else,' James said dismissively) and everyone else seemed to think she had had a very lucky escape.

There was one person, however, who seemed wholly uninterested in the potential attempted murder of his Defence Against the Dark Arts Professor, and that was Severus - who had rather more pressing things to worry about, and saw the explosion as less of a distraction and more of an opportunity for him to achieve his own goals while everyone else was distracted with the happening of the night before.

Knowing everyone was far too interested in the explosion to be interested in what he was up to, or even to notice he was missing, he put his cloak on, headed outside and walked down, past the lake, to the Whomping Willow where - keeping at a safe distance - he continued his slow circling of the tree until his sharp eyes spotted what he was looking for.

There it was, at the base of the tree, right where Black had said it would be. The knot . Though he was none the wiser as to what its purpose was or why he would need to prod it. Eagerly, he took a step forward, as if hoping closer examination would reveal some hitherto unspotted secret, but the moment he stepped towards the willow it began to creak and groan, a branch came swinging out of nowhere and - remembering that all Black might have hoped to achieve in telling Severus to come here was seriously injuring him - Severus scuttled backwards again.

The tree went still again and, from a safer distance, Sev eyed the knot up greedily. He still did not know what it did, or what might happen should he manage to prod it - as Black had been so adamant that he should - and he was still wary that prodding it may well have a cataclysmic effect which could leave him injured or dead or expelled, and Black laughing. But he needed to know.

He stepped forward again, but the tree lashed out once more and he took another hasty step back. Remembering Black's words to prod the knot "with a stick" he looked around for one which was sufficiently long. Having finally located one just within the treeline of the forest, he circled back so he was in front of the knot, sized it up, took one step forward and then - with his eyes screwed up against whatever disaster might happen next - pressed the stick into the knot.

The Whomping Willow, which had been making ominous noises at his approach and waving its branches around, seemed to freeze as if hit with Immobulus. Sev opened his eyes and stared at it in surprise.

So that was what the knot did. It stopped the tree. But what had this got to do with Lupin?

Feeling safe now the willow was frozen, he approached the trunk. He reached out and stroked the bark. Nothing happened. He circled the tree again, his fingertips in constant contact with the rough skin of the willow, tracing it, and feeling its bumps and gnarls, as he walked. As he came back around to the front, his foot suddenly slipped and his leg plunged downward. He fell flat on the ground, cursing, as his leg was twisted painfully, and apparently trapped down a hole.

He turned to look. It was a large hole… Large enough, he thought, for him to slip down. His heart beat fast against his ribcage as he decided what to do. He glanced upwards, thinking he did not know how long he had before the willow unfroze and he was decapitated by an angry tree branch, and came to a swift decision.

Ignoring the pain in his leg, he slithered down the hole and landed - with a thump - in an earthy passageway below. His heart beat faster with excitement now.

He thought he understood: Madam Pomfrey brought Lupin to the willow every full moon; she pressed the knot to freeze the willow and Lupin slithered down into this passageway ready to transform. The tree then acted as a guardian making sure the monster did not get out, and that no one noticed the secret passageway during the rest of the month.

But this was a secret passageway, and thus it must lead somewhere… presumably to the beast's cage; the monster's lair; the safehouse Lupin transformed in every month, and - hobbling along on his injured leg - Severus lit his wand and began to limp his way down the hidden tunnel.

It twisted and turned and seemed to go on for many miles (though that may have been a trick of the darkness) and then - just as Sev was thinking this tunnel led nowhere, and he was lost beneath the ground, and that had been Black's plan all along - he hit a dead end and saw a trapdoor just above his head, illuminated in his wandlight.

Almost shaking with anticipation, holding his breath and feeling like his heart was in his throat, he pushed the trapdoor open and scrambled upwards.

He was not sure what he had expected to find on the other side, but he frowned when he saw his surroundings. Whatever he had thought he would see, it was not this. He was in a house, which seemed cheerful enough. Flames burst into life and blazed cheerily in the grate as he walked into what appeared to be a living room, with squashy armchairs and brightly patterned curtains at the windows. Going out into the hall, he found a staircase and followed it up until he entered a bedroom, where once again a fire leapt into life, casting a flickering glow across the four poster bed and the honey coloured wooden furniture.

The fire, and Severus's own wand sparks, were the only light in the room - not because the curtains were closed, but because the windows were boarded up. He crossed over to one and tugged at the wooden planks which barred it, but they did not budge. He tried to peer through a crack. He could not see much, but he got the impression he was no longer in the Hogwarts grounds. There was a road outside… perhaps a road into Hogsmeade.

A suspicion suddenly gripped him. He headed back downstairs and tried the front door. But that was locked and no spell could move it. He tugged and tugged at the handle but to no avail. Eventually giving up, he returned to the living room and looked around again.

This was the Shrieking Shack. He was almost sure of it. The tunnel under the willow led to the shack, which was said to be one of the most haunted buildings in Britain… Only there were no ghosts here.

He sank down into an armchair, in front of the fire, and considered everything he had learned; turning all the puzzle pieces over in his mind. If there were no ghosts, then it was not ghosts responsible for the terrible caterwauling which had earned this building its name. And if Lupin used this place as a safe house, if he came here every full moon… if he transformed here … then it was Lupin whose howling kept the villagers awake at night.

His eyes roved around the room. It seemed a funny place for a werewolf to transform. And yet how like Dumbledore it would be to build a house and make it cosy, to try and keep up the spirits of the boy who came here to become a monster. That was exactly the sort of soft-hearted nonsense that the old muggle lover would think would matter. As if a werewolf would care what its surroundings looked like.

But, as cheerful and homely a place as it seemed, there were signs of damage that Severus's keen eyes were able to pick out. There were claw marks, gouged into the floor - blurred as if they had been repaired many times, but the spells were not quite working any more. And there were extra seams running all through the curtains, as if they had been sewn up again and again; as if a wild animal had torn them apart again and again and they had had to be fixed. Even the squashy cushion he pulled out from behind him showed signs of having been torn open, destroyed, and repaired.

Severus began to smile. So this was it. He knew the full secret now. And it was Black who had revealed it all to him: Lupin was a werewolf, and this was his hideyhole, and Madam Pomfrey and Dumbledore and Black and Potter and fat, little Pettigrew knew all about it. And he would get them all.

His smile became more satisfied. It was not long now until the next full moon, and he would return here then - camera in hand ( Lupin's camera, which was all the sweeter) - and he would get his proof. He would show the world.

And then… then that sorry, sickly, pathetic excuse for a wizard, that monster in prefect's clothing, would be history.

Unable to stop himself, Severus began to laugh.