Chapter 19: Revenge

Severus took security seriously. He completely trusted Albus' ability to ward the castle. But he also knew Black, and he knew Black would be trying to find his way in. And if he'd used the passageway from Hogsmeade once, then there was a chance he'd try to use it again. The whomping willow passageway had been warded to only let Lupin pass all year. So, as part of his curfew rounds he'd quietly go from the castle in the tunnel until he reached Albus' ward to Honeydukes and look down the passage from the Hogwarts end. He didn't expect he'd ever see Black in the tunnel, but he kept an eye out for signs that he had been there. That would at least indicate that the man was still around the castle.

He'd started his rounds before curfew, and was heading back down the tunnel to the one-eyed witch statue, once again seeing no signs of life in the tunnel. He heard voices from the corridor on the other side of the doorway. Whispered voices. It wasn't yet curfew, but chances are whispered voices were up to no good. He listened more carefully. Weasley twins. Definitely up to no good.

"Couldn't you have arranged for the elves to bring it to us, rather than we got to them?" one of them was asking.

"If I'd done that, it'd have been smaller slices, you know that they like it if we go to them. Anyway, no-one's going to see – it's nearly curfew and it's Snape's night. No-one is going to be out this close to curfew. We're only just going to make it back on time ourselves," hissed the other.

"Check the map," said one, "Filch was round the next corridor earlier." Snape heard a pause in the footsteps. Right in front of the statue. He stepped out silently. Both boys had their back to him. They were peering at something in front of them.

"All good," said George, "There's no-one…" his voice suddenly went a few register higher. "!"

Snape knew he'd made no noise but both boys turned around slowly. There was a suitable look of horror on their faces. Snape reached out and plucked the map from their unresisting fingers. "What do we have here?" he asked, in the drawl of a teacher expecting contraband. The look of horror hadn't faded.

Snape looked down, then his eyebrows went up. It was rare for a student to surprise him. In front of him was a map of the whole castle and just there, were three red dots. And one of them was labeled with his name. He looked up at the boys. It was before curfew. They were raiding the elves for cake. They weren't technically doing anything wrong. But this map! Fred swallowed. Snape looked back down at the map. He frowned and his face grew darker. He'd read the title. He looked up. The twins took a step back.

Snape turned on his heel and walked off in the opposite direction to Gryffindor tower.

"-" said Fred.

Snape marched into Lupin's quarters without knocking. Lupin was marking some first year homework for Vector. He looked up just as Snape slapped the map on the desk on top of the parchment he was reading.

"What's this, Mooney?" he asked, emphasising the nickname. Lupin looked in surprise at the map. He'd not seen that since it'd been confiscated in sixth year. "This is how you all did it, isn't it? This is how you knew where everyone was all the time?" Snape was angry.

"I think you know the answer to that is yes," he said, softly. "Where did you get it?"

"I confiscated it off the twins in a corridor just now," said Snape.

"It was open? Do you know how it works?" asked Lupin. Snape cocked his head in question.

"Mischief managed," said Lupin, tapping the map. The map reverted into a piece of parchment, a grubby piece of parchment.

Snape huffed, "Now that I've seen them with before," he said.

Lupin tapped it again, "I solemnly swear I'm up to no good," he said, and the map reappeared, centred around him and Lupin.

Snape's appreciation for a good bit of magic calmed his anger enough for him to be curious.

"That's a nice charm," he said, "Variation on a point me? Amongst other things?"

"Yes, and the obvious disillusionment charms," agreed Lupin. "You know, we had more fun making this than using it." Snape could see that.

"It didn't show people in the passages," he said. "Can it?"

"We didn't need to do the passages or the outside, but I can see where you're going with this, yes, we can alter it for that."

Lupin peered closer. "I think I'm getting old, Severus, I think I'll add a magnifying charm while I'm at it."

Next morning Snape and Lupin were testing the updated map. Lupin had realised that his need for reading magnification was actually a bonus. Usually the map was useless in the tower, there were far too many dots together to show all the dots and the names, but now there was the ability to magnify an area of the castle better.

The men were walking down towards the greenhouses, another area of the grounds that wasn't yet represented on the map when they met the Weasley twins heading towards a Herbology lesson. There was nowhere for the twins to go but to pass by the members of staff.

"I hope you enjoyed your cake," said Snape on their way past.

When the twins were out of earshot Lupin said, "That was a bit cruel. You even have the map in your hand!" Severus had told him already about how he'd stepped out of the passageway to find the twins just standing there. Lupin had had a chuckle at that.

"I will probably regret saying this, but those two are bright. They're going to make one of their own now that they know it's possible. So just get it over with and give them a couple of pointers would you? I get the feeling they might like meeting Mr Mooney."

"You have a soft spot for those two, don't you?"

"I wish they would apply their minds better, to more than pranks. They have the potential to do anything they put their minds to. But don't tell Minerva I said that!" said Severus.

It was very late. Or very early. Umbridge presumed that at 1am the last member of staff on duty had gone to bed over an hour ago. Time to have a nosey. She started in McGonagall's office, reasoning that if Dumbledore had anyone under his thumb to deal with ministry contacts it would be his deputy headmistress.

Umbridge had done some research. The portraits at Hogwarts were answerable to the Headmaster or Headmistress, but any other member of staff was seen as equal. This meant she could request something of a portrait that wouldn't automatically be countermanded by another staff member unless that staff member were Dumbledore.

"Shhh, you've not seen me, I'm just leaving a surprise thank you gift in Minerva's office. Don't say anything to her, will you? It'll spoil the surprise?"

That effectively silenced the portrait. The portraits were generally speaking cooperative with the staff, and for a surprise, well, they'd play along.

Umbridge slipped into McGonagall's office. In-tray, empty. Desk drawers, nothing. Obvious papers, none. Quick look for hidey holes, nope. Frustrated, Umbridge looked for a bit longer. Fifteen minutes later she gave it up as a bad job. Minerva wasn't Dumbledore's lackey.

"You were a while in there," said the portrait, idly, as Umbridge was leaving.

"I remembered I needed to write a note to go with it. It took time to disguise my handwriting," lied Umbridge easily. The portrait giggled. It liked a bit of fun.

By 2am, Umbridge had done Sprout and Vector's offices too. This was going to take a while and she didn't want to be up too late. She called it a night and planned to do more tomorrow. Hopefully she'd get lucky. Flitwick was a likely option tomorrow. But she had a horrible feeling that the answer was Snape, but there was a man who probably booby trapped his office. She'd rather do everyone else's first in the hope Severus' wasn't needed.

Dudley had sent off for a box of Turkish Delight and had spent the week carefully infusing them with hallucinogens. He'd spent time with the twins learning about potions. Now that had been an education! They either purchased potions or brewed their own on the quiet in a disused classroom on the sixth floor. Dudley had no idea why they didn't get Os in Potions given their knowledge, until Fred had explained that in-class potions weren't what they were interested in, but transferable technique, now that was different.

The twins had discussed with Dudley about base mixtures, acids, alkalis, reactive ingredients, and in this case minimally reactive ingredients.

"Your basic hallucinogenic potion is a wormwood base," lectured George, "But don't use too much because it's an actual poison, then you add your chosen hallucinogenic effect. For example, adding beetle eyes will have her seeing beetles. You could add nice effects, by the way, dried flowers for example. You could really trip her out if you add cheese. You know how some people have nightmares after eating cheese late at night? Well…!"

"I've had a look at additives, in the book you lent me" said Dudley, "And I've picked one," he said carefully.

"Uh oh," said Fred, "Should we be worried?"

"Boggart phlegm," said Dudley.

Fred looked at Dudley in a new light. There was depth to his creativity, it just wasn't quite channeled right.

"We did apologise to you about the boggart thing, didn't we?" checked George, hastily.

"Because that's nasty," said Fred.

"Yeah but bloody cunning," said George, "If someone else tries the sweets, they'll get a different trippy reaction."

By the end of the third week back, eight days after Umbridge had started rifling through staff offices, the student body were scared to even breathe wrong in DADA. Umbridge, lacking sleep, had become increasingly waspish and shorter than usual with everyone.

Dudley had kept the box of Turkish Delights neatly in his bag. He now needed an opportunity to get into Umbridge's office. Dudley had a feeling today was the day, she seemed a bit more incoherent than usual. Hopefully that meant she wasn't as observant.

Today's victim was Hermione. That was new. Umbridge had never gone there before.

"How dare you question my teaching?" Umbridge had demanded in a screech, advancing towards the back of the room. Dean and Dudley, sharing a row with Hermione, slid out of their seats to be away from the firing line. Everyone was staring at the back of the room. Hermione had just questioned Umbridge's method of teaching a freezing charm as a defensive technique, and today was not a day to annoy Umbridge. Flecks of spittle fired out of Umbridge's mouth, "How dare you, you nasty little child, how dare you think you know more than your betters, I am the professor here, not you..."

Dudley slid into her office and replaced the contents of her box of sweets with the contents of his, carefully adjusting for the fact that she'd eaten a few already. The ranting was still going on in the classroom. He rejoined the room to see everyone still staring at the tableau in horror. No-one had even missed him.

"You will report to the Headmaster's office for this, immediately. Perhaps he can instill a sense of respect into you,"

Umbridge hastily wrote a note, summoned an elf and ordered it to deliver the note to Dumbledore.

"Get out of my sight!"

They waited in the library for Hermione. Ron and Dudley had told the twins and Harry about their DADA lesson.

"Would he do whatever Umbridge wrote in her note?" asked Ron. They all assumed the worst.

"Given there's only one punishment she isn't allowed to carry out, I'd say he won't," said Fred, "But she answered back a member of staff and questioned their teaching publicly. She's not getting out of this scott free."

Hermione entered. Everyone checked her gait and her eyes. She seemed fine.

"Well?" asked Harry.

"Dumbledore gave me a week's detention with Filch," sulked Hermione. "He could have listened to reason!"

"Given you questioned a teacher's competence publicly, he could have taken a ruler to your backside!" said George.

Hermione flushed.

"What is with Umbridge this week?" asked Harry, "She's mental!"

"It's the weekend, perhaps some sleep will do her some good," said Ron, hopefully.

That night, Umbridge took the night off. She slept until after 11am on Saturday, and then, with a bit of clarity, decided that the last place to check, Dumbledore's office, needed more thought. She'd plucked up the courage to do Snape's the night before, but hadn't found anything.

But then she wouldn't, not that she realised it, Snape was a paranoid master spy. No-one would ever find anything. There was nothing to find, it was all in his head.

She had the house elves bring her a late breakfast, and then she felt more human again. She plotted. She definitely didn't want to get caught in Dumbledore's office. She'd need access to it from Filch too. The staff offices were only locked with an Alohamora, if they were locked at all. That should have told her something about hidden materials inside them, that is, that there weren't any, but it hadn't.

Umbridge sat in her office to think. She absently ate another sweet from her box. She must remember to buy more, the box was looking a little empty. Umbridge alighted on a winning idea mid afternoon. She went to find Filch.

"Good afternoon, Professor," said Filch as she barged into his office without knocking. Mrs Norris slunk out. There were no witnesses when Umbridge hit Filch with an Imperio.

Snape was annoyed. He was convinced someone had been in his office. There was nothing in his office other than school related things. It didn't bother him in that sense. But someone had been in his office. There was a principle to be had. He was about to read his house the riot act when he remembered the incident of the potions before Christmas. He quietly investigated instead.

"Oh," said Sprout at lunch, "You too? I thought it was just my imagination."

"I was going to say earlier in the week, but didn't bother," added Sinistra.

"Has everyone had their office rifled?" asked Snape. He got a series of nods, including from Umbridge.

"Has anyone noticed anything taken?" asked Minerva. A series of denials.

"It's just not nice to think a student is going through our desks," said Sprout, upset.

"When I find who went through mine, I'll make use of the slipper I keep in it," said Flitwick.

Having found out the staff offices had been searched, and it was likely to continue, given they'd been searched on multiple nights, Severus spent that evening watching the map. Red dots eventually cleared the corridors, then they went to their dorms.

Miraculous! Not a single student out of their common room and dorm areas, thought Severus, watching the map like a hawk. Anyone would think they were cherubs. But give it time, on a Saturday night they went to bed, but then they got up again, thinking the staff were asleep.

There it was, the first idiot out. He was pleased it wasn't one of his, and was surprised it wasn't one of Minerva's. Filius would be annoyed. Severus watched the dot move towards the Hufflepuff common room. He looked closely at the name, ah yes, if he magnified Hufflepuff one person was in the common room and not their dorm. Two seventh years planning a late night 'study session', otherwise known as making out on the sofas.

Snape summoned an elf. "You'll find a seventh year on the corridor headed towards Hufflepuff, could you pop him straight here?" asked Severus, pointing to a spot in front of his desk." The house elf smiled and popped away. Snape had time to sit behind his desk and school his features into bat of the dungeons before the elf popped a very surprised James Brocklehurst into his office and popped away again.

"Mr Brocklehurst, late night outing is it?" asked Snape.

James opened and closed his mouth. He was still in shock from walking along the corridor turning into standing in front of Snape's desk.

"What do you think your head of house feels about you being out after curfew?" asked Snape. "An answer, please."

"I think he'd not be very happy about it," answered the boy awkwardly.

"And what do you think he'd do about that?" continued Snape, "Answer honestly, please."

Brocklehurst swallowed. "I think he keeps a slipper in his desk drawer, sir," he said reluctantly.

"Well today's your lucky day, Mr Brocklehurst," said Snape, "I don't." The boy visibly relaxed.

"I keep a ruler in mine."

After James had been dismissed from his office, Snape went back to looking at the map. There was nothing out of the ordinary. It was Vector's and Sinistra's curfew rounds this evening, and they were patrolling as you'd expect. He saw another red dot, but that was just Filch. He smiled, even Mrs Norris had a dot.

Snape carried on watching the map, focussing on the four common rooms and the staff's offices. After twenty minutes he was intrigued. Filch was in Dumbledore's office. While Filch, as caretaker, could and did go anywhere, it was odd that he'd been in there so long. Snape carried on watching. He magnified the map to see the actual office in detail and where inside it the dot was moving. It wasn't moving, it was stationery where Dumbledore's chair would be if it were actually on the map. Odd grew into suspicious. Severus picked up the map so he'd still be able to look for other people out and about, and made his way to Dumbledore's office.

Mrs Norris was outside. Normally Mrs Norris didn't like Snape. Usually she loudly made his presence known. This time, Mrs Norris silently watched him enter Dumbledore's office instead.

"Good evening, Argus," said Severus. Filch looked up from the papers he was reading at Dumbledore's desk. He didn't look surprised, or guilty. He just looked up, absently. "Interesting reading?" growled Severus, angry on Dumbledore's behalf that the caretaker was rifling through his things.

"I'm looking…" said Argus, he tried again, "I'm…" There was another pause, "I can't find it," he said.

Severus looked more closely. Argus' voice wasn't right. There was something wrong. "Argus, can you stand up and come here, please?" said Severus, gently. Argus complied. Severus looked him carefully in the eyes. He'd seen that look before.

"Finite incantatem!"

Filch blinked in confusion. He looked around. "Why am I here?" he asked.

"You were cleaning, I came in looking for some papers I'd left with Dumbledore to sign, I know it's late, I must have surprised you. You banged your head," lied Severus. "Come on, I'll make sure you get back to your quarters." Severus escorted Filch back to his rooms, keeping an eye out for any surprises. He then warded Filch's door. He would be alerted if anyone went inside. He nearly went to find Vector and Sinistra to see if they'd seen anything, but he knew they hadn't, the map was accurate.

Early next morning, thankfully Sunday so there were no classes, Snape summoned an elf to wake Dumbledore and the two met in Dumbledore's office at 6am. Snape had left the papers on the desk as he'd seen Filch looking through them, and therefore Dumbledore was alerted to something having gone on in the night as soon as he reached his office.

"What's this?" asked Albus, indicating his desk.

"There's been an incident," said Snape. "There was no point in waking you last night, I had a full view of whatever there was to see, not that there was anything to see. Let me tell you about my evening…"

After Severus had explained everything he knew, Albus sent for Filch. "Good morning, Argus, Severus tells me you had a knock to the head last night, are you well?"

"I think so, Headmaster," said Filch gruffy, "But I think I must have banged my head pretty hard, I can't remember everything."

"What can you remember?" asked Albus, gently.

"Well, I can remember having lunch yesterday, but not much after that. I think someone came to visit my office, but I don't know who," he said.

"Think carefully, Argus," said Dumbledore, "I don't want to frighten you, but was it Sirius Black?" Argus' eyes bugged out of his head.

"N… n… no…., Headmaster, I definitely think I'd remember that."

After Filch had left Dumbledore's office, Dumbledore summoned the rest of his senior staff and Lupin. He explained what had happened, and raised his concern that the perpetrator might not have been Black. They had no idea when Argus may have been hit with the imperious. He could have been told to go about his normal day and only act out of character at night. By the same token, it could have been the day before yesterday. They thought it unlikely he'd have been cursed much earlier than that because imperio'd people tend to act odd and others would have noticed. But chances were, at some point yesterday someone cursed Filch.

"But what is someone looking for?" asked Minerva. "Why search staff offices, and then yours? The only reason Argus was used to search yours is because you lock yours properly. This must be the same person." Everyone nodded their agreement to that.

"And, is it a student, or a member of staff?" asked Severus.

"Severus!" exclaimed Minerva, offended, "You're suggesting that one of our colleagues rifled through our things?"

"Are you suggesting it's the students?" demanded severus, using the same tone right back.

"Professors, please!" said Albus, keeping the peace.

"I was thinking of one particular staff member to be precise," said Severus. "The toad."

"I can't exactly spy on my own staff, Severus, and the direct approach isn't going to work," said Albus.

"Then I will keep an eye on her. She doesn't know about the map."

Albus nodded. "Don't get caught please, I don't want the hassle."

Snape just raised an eyebrow at him. "While she's been acting a little more paranoid than usual this week, I'm sure I'll be fine."

At lunch that day, the staff table was being scrutinised a little more carefully than usual by the students. Most of those looks were aimed at Severus.

"What's that about?" asked Minerva quietly to Severus.

Filius answered for him, "It appears Severus has expanded his reputation during the night to include omniscience."