"The Chamber of Secrets has been opened again."
Kavell spoke drunkenly.
"You know the legend of the Chamber of Secrets, right?"
Sherlock replied casually,
"Hogwarts founder Salazar Slytherin had irreconcilable differences with the other three founders. He believed Muggle-born students were unworthy of learning magic at Hogwarts, so he constructed the Chamber of Secrets. Inside it, he hid a terrifying monster, waiting for his heir to one day open the chamber and purge the school."
He blinked and fixed his gaze on Kavell.
"How do you know the Chamber has been opened now?"
Kavell stabbed his steak with his fork and bit into it with exaggerated gusto.
"My grandson is a sixth-year at Hogwarts. Dumbledore may be trying to keep things quiet, but news like this doesn't stay hidden for long."
Sherlock paused thoughtfully. He vaguely recalled a sixth-year Hufflepuff student with the surname Kavell.
"But why do you say again? When was it opened before?" he asked softly.
Kavell let out a smug chuckle.
"Haha… this is one of those stories I always end up bragging about when I drink…"
He quickly finished the rest of his steak, smacked his lips, and continued.
"It was about fifty years ago… maybe a bit less—my memory's not what it used to be. Back then, Dumbledore was just a Transfiguration professor. You-Know-Who was still nobody important, and Hogwarts was hit by a series of strange attacks."
"A student died. It caused a huge uproar. Everyone said the Chamber of Secrets had been opened—that someone had released Slytherin's monster to cleanse the school."
This was the first time Sherlock realized that the current incident wasn't the first. The Chamber had been opened once before.
He frowned slightly.
"And then?"
"Then it just… stopped," Kavell said with a shrug. "No one really knows why. The Headmaster at the time claimed the death was an accident. No one believed it—but the attacks ended. Still, one student was expelled that year."
"The attacks stopped after that student was expelled?"
Kavell leaned forward slightly, lowering his voice.
"Use your brain a little, Watson. It's obvious—the expelled student had something to do with it."
Sherlock's attention sharpened.
"What was that student's name?"
Kavell burped. Despite his drunkenness, he remembered this part clearly.
"That student was expelled fifty years ago… yet he never truly left Hogwarts. Even now, Dumbledore trusts him completely. Honestly, I've always thought Dumbledore's judgment of people is questionable…"
He didn't keep the suspense any longer. Reeking of alcohol, he blurted it out:
"Rubeus Hagrid. Keeper of Keys and Grounds at Hogwarts. One of Dumbledore's most loyal men."
Sherlock froze.
It took him several seconds to recover.
"And how do you know all this?" he asked, his tone now serious.
The alcohol was catching up with Kavell. His eyelids drooped.
"How do I know? Hagrid was my classmate… Back then, he wasn't a bad guy… just obsessed with strange creatures…"
His voice trailed off into incoherent mumbling.
But Sherlock had already heard enough.
He had never once suspected Hagrid. With his personality and demeanor, it was almost impossible to associate him with the Heir of Slytherin.
Sherlock stood up. Kavell's snores had already begun.
He took out the remaining tuition fee and placed it neatly on the table.
The lesson itself wasn't worth that much—but the information he had gained certainly was.
Kavell had intended to befriend him, but Sherlock had no intention of revealing his real identity. Paying the full amount would keep things clean between them.
Without lingering, Sherlock left the cabin. Instead of using Floo Powder, he returned to the field where he had practiced earlier.
"Apparate."
His body vanished into the cold air, reappearing moments later in a secluded alley in Hogsmeade.
He removed his disguise, slipped his glasses into his pocket, and stepped out onto the main street.
As he walked, he ran into several professors.
"Oh, Sherlock? When did you come out?" Professor Sprout asked.
Beside her stood Professor Sinistra and Professor Burbage.
Sherlock's expression returned to its usual calm indifference.
"This morning. I went to the Owl Post Office to handle some matters."
Professor Sinistra smiled.
"We're heading to the Three Broomsticks for afternoon tea. Care to join us?"
Sherlock instinctively wanted to refuse—but after a brief pause, he nodded.
The tea was uneventful. He spoke little, simply accompanying them for a couple of hours before politely excusing himself and returning to Hogwarts.
That afternoon, younger students filled the corridors, laughing and playing.
Sherlock didn't return to his office. Instead, he walked straight to the stone gargoyle guarding the entrance to the Headmaster's office on the third floor.
"I need to see Professor Dumbledore."
The gargoyle remained silent for a moment, as if awaiting permission.
Then, with a low rumble, it shifted aside—granting him entry.