Hermione Granger
It was a late evening when Hermione, utterly humiliated and traumatized, returned to the base.
Her mission, investigating whether Michael Brown was the heir of Slytherin, ended disastrously. Not only was she instantly seen through by her target, rendering the whole point of brewing a polyjuice potion meaningless, but she was also kidnapped and blackmailed into staying quiet by the very same madman she was trying to expose. This was practically the worst conclusion she could imagine.
The worst part was that she couldn't even say that her failure was solely Brown's fault. Hermione knew that it was her overconfidence and lack of preparation that led to the mission's failure. She had not prepared enough to play the role of Luna Lovegood, deciding that it was safe to approach Brown after listening to Lovegood for an hour and having one brief conversation with her. It was her hubris that led to her downfall.
It obviously didn't mean that she forgave Brown, far from it. He was a horrible, sadistic bastard whose goal seemed to be to ruin everything around him and mock Hermione's every effort. Apparently, he saw nothing wrong with rendering Hermione unconscious and tying her to a damn chair! He was a menace, spreading corruption with his every action! He had to be stopped!
Her life, however, seemed like some kind of sick joke, as she wouldn't be able to do it herself. Apparently, Brown was competent enough to enchant the recorder to work on magic, using it to blackmail her into compliance! How dare he?! She had been called a mudblood in the past, and it was still not as cruel as what was taking place now!
She would have been able to put up with it if it was just her, but she knew she would also disappoint the boys, who were probably able to complete their part of the mission without a hitch. She just hoped they would forgive her incompetence.
Hermione immediately forgot about her worries, however, when she entered the classroom where she, Harry and Ron were to reassemble. It only took her one look to know that something had gone wrong.
Contrary to her expectations, she found Harry and Ron in a state of complete panic. For some reason, an aura of defeat and fear surrounded the boys, as they were sitting in the corner of the room with haunted expressions on their faces, unable to cope with the extreme emotions they were clearly experiencing. Harry was mumbling something under his breath, his face constantly alternating between fear and anger, while Ron was staring blankly at the wall, shaking every few seconds.
Whatever spooked them so much must have been terrifying, because it took them a few seconds to even notice her arrival. However, when they finally did, the boys hurriedly reached for their wands, ready to protect themselves, stopping only after recognizing that it was Hermione who entered the room. They calmed down upon recognizing her, though only slightly.
What in the world happened while she was gone?!
"Hermione! Thank Merlin, you're alright!" shouted Ron, for some reason convinced that she was in danger. The relief in his eyes shocked Hermione, as she had no idea why they were acting so strangely. They shouldn't know about her failure yet. "We were so worried!"
"Of course I am alright. Why would you think I'm not?" Hermione asked, confused by their behaviour. Until now, she was sure she had had the worst day in the group, but it was becoming increasingly clear it wasn't true "More importantly, what happened to you? Why are you so nervous?"
"...You don't know" whispered Ron quietly, realizing something. After he and Harry exchanged a brief glance, apparently unsure how to broach the subject with her, Ron gathered his courage and said in a trembling voice "Hermione... Malfoy was petrified today."
"...What?" asked Hermione, stunned by the news. How was this possible? She had spent the evening with Brown, so he wouldn't have been able to... wait, how long had she been unconscious? She furrowed her eyebrows, and a horrible suspicion rose in her mind. She looked at Ron and asked a very important question "...how did this happen?"
"As planned, we went to talk to Malfoy, but we found him petrified in the bathroom, looking in the mirror with a horrified expression on his face! There was also a message from the Heir above him, clearly left there to mock us!" Harry practically shouted, sounding both angry and frightened at the same time, making it clear that he was still shaken by the events that had taken place "As if that wasn't enough, he had apparently petrified Crabbe and Goyle, too! Somehow he knew where we hid them and went there to petrify them!"
"That's terrible!" exclaimed Hermione, horrified by the implications. It was proof that the heir knew about their plan all along! He even knew where to find Crabbe and Goyle! Wait a minute... if he knew about their plan, didn't that mean that he also knew about the polyjuice potion? Just like certain someone...
"And that's not even the worst of it!" Ron shouted, bringing Hermione back to the present "People saw us... I mean, they saw Crabbe and Goyle coming out of the bathroom after... after the real Crabbe and Goyle were petrified! Parkinson and Bulstorde saw our polyjuice slowly wearing off! We had to run away before they could recognize us!"
...People think that Malfoy was petrified by someone, who used a polyjuice potion to approach him? Didn't that mean...
"And it's clear that the heir had alerted the teachers beforehand! They came too fast for it to be a coincidence! If it weren't for the invisibility cloak, they would have caught us! We had to spend almost an hour hiding under it, waiting for the teachers to finally leave!" Harry added, full of righteous fury "It's obvious that we are being framed here! Not only that, the heir decided to petrify the entire git trio during our investigation, but he also did everything to set us up!"
Hermione was barely listening, becoming increasingly aware how much she messed up by approaching Brown. Dread filled her whole body.
The boys continued talking, unaware of her growing despair.
"...Well, at least we now know that Malfoy is not the heir of Slytherin. That's something, right?" Ron asked with a fake cheer, desperately trying to find some Silver lining in their situation. He then grimaced, realizing something "Wait, doesn't that mean that our prime suspect is now Michael Brown? Bollocks"
"Well, I guess so, but...wait, Hermione, we forgot to ask. How was your..." Harry began speaking, only to fall silent upon seeing Hermione's pale face and trembling body "What happened?!"
"...we...might be in a lot of trouble" Hermione replied weakly, only now comprehending the true cunningness of Brown's plan. He planned everything from the very beginning! Lovegood was obviously working with him, that's why she gave them her hair! After Brown knocked her out, he petrified Malfoy, Crabbe and Goyle, framed Harry and Ron and returned to her, extracting a confession from her! He was a brilliant monster, carefully manipulating everyone around him for his selfish ends!
She had doubts before, but now she was sure. Michael Brown was the heir of Slytherin!
...And now, thanks to Hermione, he had everything he needed to doom them.