The first meeting was a disaster wrapped in a professional veneer.
Kingsley laid out the facts. The chamber, now dubbed the "Aethelred Vault," had been discovered behind a wall that had crumbled during repairs to the lowest dungeons. Every diagnostic charm cast upon it fizzled, died, or, in one alarming case, rebounded and turned the caster's hair bright blue for a week. It was magically inert and yet overwhelmingly present, a paradox that had the entire Department of Mysteries stumped.
"Your primary objective is not to breach it," Kingsley stated, his hands flat on the table. "It is to understand it. To determine if it's a threat, a treasure, or simply a historical curiosity we've forgotten. You will report directly to me. Any attempts to open it require my direct, written authorization. Is that clear?"
"Perfectly," Hermione said, her quill already scratching notes on a fresh piece of parchment.
Cassian merely gave a curt nod, his arms crossed. He hadn't taken a single note.
Once Kingsley left, the air in the room turned thick and heavy. Hermione looked at Cassian expectantly.
"Well?" she prompted. "As co-leads, I assume we should start with a research methodology. I propose we divide the known historical texts—pre-Founder era magical theory, focusing on ward construction and symbiotic enchantments. I'll take the British and Nordic collections, you can start with the Mediterranean and African archives—"
"Or," Cassian interrupted, his voice flat, "we could actually look at the thing."
Hermione blinked. "Without a proper foundational understanding? That's how people get themselves killed or worse."
"A foundational understanding built on what?" he challenged, finally turning to face her fully. "Books written centuries after the fact by people who likely never knew the chamber existed? That's like trying to understand a thunderstorm by reading a poem about rain. You need to feel the magic, Granger. Not just read about it."
"That is a reckless and intellectually lazy approach," she shot back, her cheeks growing warm.
His eyes narrowed. "Lazy? I've dismantled curses in Egyptian tombs that would make your Hogwarts curriculum look like a children's picture book. You learn by doing. By touching. By listening."
"This isn't a tomb! It's beneath a school full of children!"
"Which is why we need to know what it is, not just what a bunch of dead theorists think it might be." He stood up, his chair scraping against the stone floor. "I'm going down to the vault site this afternoon to set up my own diagnostic equipment. You can join me, or you can stay here and…" He gestured vaguely at her pile of parchment. "File your notes."
He was out the door before she could form a retort. Hermione sat fuming, her knuckles white around her quill. Arrogant, insufferable, condescending… The words circled in her mind. She took a deep breath. He was trying to get a rise out of her, to establish dominance. She wouldn't give him the satisfaction.
She spent the next three hours in the Ministry library, pulling every relevant text she could find. But his words nagged at her. You need to feel the magic. It was infuriating because there was a kernel of truth in it. The books were silent on the specific, humming paradox of the Aethelred Vault.
With a sigh of frustration, she packed her bag and headed for the Floo network. Fine. She would go to the site. If only to prove to him that observation without preparation was folly.
---
Hogwarts felt different now. It was home, but a home that had moved on without her. The suits of armor nodded as she passed, and Peeves cackled somewhere in the distance, but the air was lighter, free of the pervasive fear that had haunted her seventh year.
She made her way down to the dungeons, past the Potions classroom, and into a corridor she barely recognized. It was newly rebuilt, the stone still pale and clean. At the end stood a heavy, reinforced door where two Aurors were stationed. They nodded respectfully and let her through.
The chamber beyond wasn't large. It was a rough-hewn, circular space, clearly natural, not built. And in the center of the far wall was the Vault.
It wasn't a door. It was a seamless, dark metallic surface, like obsidian but with a faint, swirling, milky quality deep within its heart. It hummed. A low, sub-audible thrum that she felt in her teeth and in the bones of her wrists. It was cold, a deep, soul-sucking chill that had nothing to do with the dungeon air.
Cassian was there, as promised. He'd shed his outer robes and was in simple black trousers and a white shirt, the sleeves rolled up to his elbows. Various strange, brass instruments floated around him, their delicate arms moving slowly, taking readings. He didn't look at her as she entered.
"See?" he said, his back to her. "You can't get this from a book."
Ignoring him, Hermione approached the Vault slowly. She pulled out her wand. "Revelio."
The spell hit the dark surface and dissolved into a shower of harmless silver sparks that died before they hit the floor. Nothing.
"Told you," Cassian muttered.
"Specialis Revelio! Historica Veritas!" she tried again, with the same result.
"Your little party tricks aren't going to work on this, Granger." He finally turned, a small, twisted smirk on his face. "It's not listening."
"What is your equipment telling you?" she asked, forcing her voice to remain level.
"That it's old. Very old. And that it's… sleeping." He looked back at the Vault, his smirk fading into a look of intense concentration. "The magic isn't active. It's dormant. That hum is its heartbeat. The real magic, the one that built this, is still asleep."
"How do you wake it up?"
His stormy eyes flicked back to her. "Who said we should? Waking a sleeping giant is generally a bad idea. Especially when you don't know if it's a friendly giant or one that likes to eat wizards for breakfast."
For the first time, they were in agreement. The realization was so startling she almost smiled. She stopped herself.
"So, we observe. We learn its patterns. We try to understand its nature without provoking it," she summarized.
"Exactly." He looked at her, and for a brief second, there was no animosity in his gaze, just a shared, professional curiosity. "You're not completely hopeless, then."
And just like that, the moment shattered.
"I'll have you know—" she began, her temper flaring.
But he had already turned back to his instruments, effectively dismissing her. "I'll send you my readings tomorrow. You can compare them with your… books."
Fuming, Hermione spun on her heel and left. He was impossible. Absolutely impossible.
Yet, as she walked back through the castle, the low hum of the Vault still vibrating in her bones, she had to admit—to herself, and only to herself—that he was also, infuriatingly, right. This was a problem you had to feel. And she had a sinking feeling that solving it was going to mean feeling her way through a great deal more time with Cassian Thorne.