Thursday passed the same as Tuesday did, since it was the identical day for classes, and Harry did his detention that night. The next day was Friday and that was double Potions class in the morning. When he brought his trunk, no one seemed to pay him much mind. He gave Neville his things and handed Hermione her backpack, then sat down.

Professor Snape strode into the room and the door shut behind him. He didn't speak when he reached the front of the room, tapped a stack of parchment, then swiped the wand towards the class. The papers fluttered out through the air and they all floated to each student. Some tried to catch them and fumbled it, while the smarter ones, like Harry and Hermione, waited for them to land before trying to grab them.

T? Harry asked himself. How did I get Troll for a mark?

“As you can see... most of you were... acceptable in your potion making.” Snape said and glared at the class as he folded his arms under his black cloak. “However, some of you were less than expected.” He said and his eyes met Harry's.

Harry turned his head slightly and blinked his eyes as he concentrated on the potion recipe, then he put his hand up into the air.

“Yes, Mister Potter?”

“I made the best potion in the class. Why did I get a T?” Harry asked and there were gasps, chuckles, and a lot of whispering.

“Quiiiiet.” Snape said to the class to hush them and looked back at Harry with an intense glare. “I do not appreciate students that perform pranks on me.” He said. His instant anger at the prank last Friday had settled during the week and had folded right into his hatred for James Potter, Harry's father.

“I didn't...” Harry started to say.

“Did you or did you not put a sticking charm on your vial when you placed it in the box?”

“I did.” Harry admitted and a few more gasps met this admission.

“Ten points from Griffindor.” Snape said with a sneer. “I would dock you even more... if you hadn't been lucky enough for me to leave grading your potion until last.” He picked up the box that was full of glass shards and walked over to Harry. His potion was still in the crystal vial and hadn't even been opened. “If you dare try to prank me again...”

“I only stopped it from falling out of the box like it did the first time.” Harry said, truthfully. “It's not my fault you didn't check it.”

Snape glared at him and put the box down on his desk with the sound of rattling glass. “You will surrender your own vials as replacements for all of the vials you broke and will apologize to the other students.”

“Why can't I just repair these and give them back?” Harry asked.

“You won't learn anything if it was that easy to fix things.” Snape said and managed to not sneer at him. “I also forbid you from buying more crystal vials. You will use these for your potions from now on.” He said and shook the box.

The Slytherin students laughed and Snape didn't bother stopping them this time.

“Fine.” Harry said and stood up. He opened up his case of crystal vials and gave one to Hermione beside him. “I'm sorry yours was broken.”

Hermione opened her mouth to refuse and Snape spoke.

“All students must keep the new vials. You cannot give them back.” Snape said and looked at Harry. “Hurry up.”

Harry walked around the class and gave each student a crystal vial and apologized. He ignored the laughs and jeers from the Slytherins and went back to his seat. Snape looked into the case and saw that there were still eight unused vials and one still in the potions box. He took them and pocketed them while Harry gave him a sightly angry face.

“Good luck holding potions in all those broken bottles, Potter!” Draco said as he tossed his new crystal vial into the air and caught it. Everyone laughed.

“You mean these perfectly fine ones?” Harry asked and waved his wand over the box. “REPARO!” He yelled and the loud sound of tinkling glass filled the classroom. A moment later, Harry picked up one of the now intact vials and looked right at Professor Snape. “You said I can't buy replacements.”

“Correct.” Snape said and ignored the fact that Harry had repaired all of the vials and not just one.

“Then I'll make them myself.” Harry said. “Mutatio Crystallo!”

To everyone's surprise, the glass vial morphed and became an expensive crystal one. Harry picked up each of the nineteen vials and performed the same spell. He didn't stop there, though.

“Indossolubus!” Harry said and the crystal vial in his hand glowed for a few seconds.

Severus Snape's mouth opened slightly in surprise as Harry performed the Unbreakable Charm, then he proceeded to do it to each of the nineteen vials. The students looked on in confusion, not realizing what Harry was doing. Only Hermione knew and she watched attentively as he did them all. She was going to have to practice the spell herself and do her own vials as soon as she had the chance.

That was when Snape realized that crystal vials didn't come in an unbreakable version, no matter how much you wanted to spend on them. It was considered too much of a waste of time to cast such strong magical spells onto something so small and was usually reserved for important potions that needed to be protected. It wasn't meant for every day potions use or to be used by students.

Harry put his 'new' crystal vials into the case and sat down when he was done. He would buy more glass vials to fill up the rest of the spots and transfigure them, too. He would send an order right after class for them, since the professor stole the rest of them.

Snape did his best to not glare at the boy. “Today's potion.” He said and tapped the chalkboard with his wand, once again breaking his word that there would be no wand waving in his class. “You will require all of the remaining time to brew it.” His eyes roamed over the students. “Get to work.”

“We're not working in pairs?” Someone asked.

“No. You will all be individually marked.”

“Fairly?” Harry asked.

“Harry!” Hermione gasped.

Snape glared down his nose at him. “Five points from Griffindor for your cheek, Potter.”

Harry stood up and used the water charm to put some water into one of his crystal vials. He corked it and walked up to the desk. “Here's my potion for you to mark, professor. You can keep the vial this time, since you seem to like stealing them from me.”

Gasps and mutters came from the other students as he walked back to his desk. He waved his wand to pack everything and surprised the class, then he picked up his trunk by the handle.

“I'm sorry I can't carry your things this time.” Harry said to Hermione, nodded at Neville, and walked out of the class.

*

Filch was very surprised when Harry knocked on his door half an hour after first class began. “Lad, what is it?” He asked in concern, then he scowled. “Don't tell me there's a mess somewhere!”

Harry smiled. “No, I finished my potion and left class early.”

“Oh. That's alright, then.” Filch said.

“Meow!” Missus Norris said and darted out to wrap around Harry's leg.

“It's really nice to see you, too.” Harry said and held a hand down for her. She used his fingers like a comb and rubbed her head on them, so he wiggled his fingers to give her a good scratching.

“Today we tackle the bathrooms.” Filch said and handed Harry some of the necessary tools.

“That's not too bad, is it?” Harry asked and Filch laughed.

“Do you know how many students there are?” Filch asked.

Harry had to think about that. “Well, if there's only ten students a year for seven years and four houses... that's about three hundred.”

“A bit basic; but, good reasoning.” Filch said. “Some houses get more than the others some years and some won't get any at all.”

“Really?” Harry asked as they left the office and walked down only a few doors.

“Aye. That was years ago, though. I think the hat sorts fer balance now.” Filch said and they went inside the bathroom.

“How is the hat?” Harry asked and put down the cleaning tools and put on the rubber gloves Filch handed him. He had completely forgotten about the hat that he had talked to at the sorting ceremony.

“It's sitting inside a glass case inside the headmaster's office.” Filch said. “It doesn't want to get dirty.”

Harry smiled. “It did say it had never been cleaned before.”

Filch barked a laugh and nodded. “Understandable. Most people would be afraid to wash old Griffindor's hat.”

“That's what the hat said.” Harry said and they both started cleaning the stalls.

“Me-ow meow.” Missus Norris said from the sink she had perched on.

“Aye, lass. It would be nice if it could bathe itself like you.” Filch said.

Harry chuckled. “The rip on the hat for the mouth is huge! How big would the tongue be to lick itself?”

Filch and Missus Norris looked at him for a second, then they laughed and meowed in amusement.

*

Later that day, Snape entered Dumbledore's office. “Headmaster.” He said and came to a stop beside the large desk. “You called for me?”

“Yes, I did.” Dumbledore said. “I've been hearing some disturbing things about you and Harry.”

Snape's mask slipped and he showed the old man anger for a moment, then he returned to his calm demeanor. “What lies has the boy been telling you?”

Dumbledore looked at Severus for several moments, then he sighed. “He hasn't told me anything.”

“Then who did he...”

“He hasn't told anyone anything.” Dumbledore said. “He hasn't complained to anyone since his outburst last week in the Great Hall.”

Snape crossed his arms under his cloak. “How did you find out?”

“Several students overheard the Slytherins talking about what happened in Potions class this morning.” Dumbledore said. “It was quite disturbing.”

“He is an arrogant child and he is full of himself.” Snape said. “He caused me to smash all of the other students potions with his prank.”

Dumbledore looked at Snape sternly for a moment. “From what I heard, it was you that caused it. Vials don't jump out of boxes on their own, do they?”

Snape didn't say anything in response.

“That wasn't what was disturbing.” Dumbledore said. “He transfigured glass vials into crystal.”

“Yes.” Snape said. “Quite easily, in fact.”

“I talked to Minerva already and he hasn't been taught that spell.”

Snape stayed quiet.

“I think it is time I gave you something to do.” Dumbledore said and it was Snape's turn to sigh. “Now, now. It's not that bad.”

“It's going to be... excruciating... if you say it like that.” Snape said.

Dumbledore smiled. “I want you to find out everything there is to know about Harry Potter.”

“No.” Snape said.

“I need to know, Severus.” Dumbledore said. “Please. Find out what you can.”

Snape let the mask fall again and glared at the old man. “You know I'm going to hate every second of this.”

“Yes.” Dumbledore said and refrained from telling him that was what made him the perfect investigator. He will dig everything up precisely because he hates the boy. “Please report everything you discover.”

“Yes, headmaster.” Snape said and left the office with a swish of his cloak.