Chapter Text
Chapter One: When Lightning Refuses to Leave
The owl did not die.
It unraveled.
One moment it was beating its wings steadily through the Auror Office windows, the next it burst apart into a spiral of saltwater mist and white feathers that dissolved before they touched the floor.
Ron swore loudly.
Harry didn’t flinch.
Hermione was already moving.
She caught the falling parchment before it hit the stone tiles, ignoring the seawater dripping onto her sleeves. The ink shimmered faintly, letters shifting across the page like something alive beneath the surface.
“It’s not cursed,” she murmured. “It’s ancient.”
Ron stared at the evaporating puddle. “Ancient like goblin-made ancient, or ancient like we-should-evacuate-London ancient?”
Hermione’s eyes scanned the text as the symbols rearranged themselves from Greek into English.
Her expression hardened.
“Greek.”
Harry leaned back slowly in his chair. “That’s worse, isn’t it?”
“Yes.”
She read aloud.
To the Wandbearers of Britain,
Olympus invokes parley.
A forge-born weapon has crossed realms.
It answers ancient magic.
It has rooted beneath your stone.
Three demigods will arrive.
Do not antagonize them.
Ron blinked twice.
“Demigods,” he repeated faintly.
Harry rubbed his forehead. “When?”
The Auror Office windows rattled violently.
Hermione didn’t look up.
“Now.”
—
Hogwarts had endured war, siege, dragons, giants, and Basilisks.
It had never endured a storm that refused to move.
Lightning forked across a tight spiral of cloud directly above the Black Lake, but it did not strike. It coiled. It lingered. It waited.
Students clustered along the courtyard walls, whispering anxiously. Professors stood tense near the steps.
McGonagall’s expression could have shattered granite.
Harry, Ron, and Hermione stood beside her — not as children of the castle, but as its protectors.
The lightning tightened.
Condensed.
Then three figures stepped out of it like descending a staircase no one else could see.
They didn’t fall.
They landed.
The boy in the center rolled his shoulders as though dropping from the sky was mildly inconvenient.
He had messy black hair, sea-green eyes, and a bronze sword strapped casually to his back.
He took one long look at Hogwarts’ towering spires.
“…Okay,” he said. “That is aggressively Gothic.”
Ron muttered, “I hate him already.”
The boy beside him — taller, sharper, dressed in dark combat gear with intense dark eyes and an aura that excluded death — scanned the castle grounds with the focus of someone cataloguing exits.
The grey-eyed girl moved like a strategist even at rest.
Hermione stepped forward first.
“Hermione Granger. Ministry liaison.”
The black-haired boy grinned.
“Percy Jackson. Son of Poseidon. Sorry about the storm — I parked it.”
Ron spluttered.
“Parked.”
McGonagall’s gaze remained steady. “And you will un-park it?”
“Eventually,” Percy said cheerfully. “We’re looking for something first.”
Hermione’s pulse tightened.
“Under the castle.”
Percy’s grin faded slightly.
“Yeah.”
From the edge of the courtyard came a familiar, controlled drawl.
“How reassuring that Olympus sends children.”
Hermione did not turn.
She felt him.
Draco Malfoy descended the steps with measured elegance, black coat precise, expression composed to the point of provocation.
Percy tilted his head.
“Oh. Blond one’s got attitude.”
Draco’s eyes flicked over him coolly. “And you have sea salt in your boots.”
Annabeth — because that had to be her — narrowed her eyes thoughtfully at Draco.
Assessment.
Hermione caught it.
And something uneasy stirred in her stomach.
—
The meeting room was layered in protective wards within minutes.
Percy paced as if sitting still physically pained him. Annabeth stood by the window studying Hogwarts’ layout like a puzzle. The blonde boy — Nico, Hermione learned — remained silent, shadows subtly leaning toward him like they preferred his company.
Harry folded his arms. “Explain.”
Annabeth stepped forward.
“A weapon forged by Hephaestus vanished from Olympus three days ago. It reacts to ancient magical systems — not just divine magic.”
Hermione’s mind raced.
“Hogwarts’ foundations predate Roman expansion,” she said slowly. “There are chambers beneath the castle older than recorded wizarding history.”
Percy nodded. “We felt it the second we crossed the Channel. It’s anchored.”
“Anchored how?” Ron asked warily.
Percy glanced toward the Black Lake.
“Like something’s feeding it.”
A cold silence settled.
Draco leaned back against the wall.
“And you assume we’ll allow demigods to wander through the foundations of our most historically significant magical structure?”
Percy met his gaze evenly.
“You could try stopping us.”
The air tightened.
Hermione stepped between them before it escalated.
“No one is stopping anyone,” she said calmly. “But we will not permit reckless excavation.”
Annabeth studied her closely.
“You’re the one in charge.”
Hermione hesitated only a fraction of a second.
“Yes.”
Draco’s gaze shifted slightly at that.
He knew better.
—
Later that night, the storm remained suspended above the lake.
Hermione stood alone in the Astronomy Tower, watching lightning trace silent veins across the sky.
She heard the footsteps before he spoke.
“You’re avoiding the demigods.”
“I’m thinking.”
Draco stepped beside her, close enough that their sleeves brushed.
“You’re concerned.”
“Of course I am. A god-forged weapon is embedded beneath Hogwarts.”
He lowered his voice.
“That isn’t what worries you.”
She exhaled slowly.
“They destabilize things.”
“Things?” he pressed.
Her eyes met his.
“Us.”
The word lingered.
Their relationship had survived war, political fallout, public scrutiny — but only barely. It lived in glances and hidden rooms. In restrained touches. In carefully constructed deniability.
Percy Jackson was observant.
Annabeth was worse.
“They don’t matter,” Draco said quietly.
“They will,” Hermione replied. “They always do.”
Footsteps echoed on the spiral stairs.
They stepped apart instinctively.
Percy emerged into the moonlight.
“Oh,” he said, blinking between them. “Did I interrupt intense British brooding?”
Hermione straightened immediately.
“Security inspection.”
Percy grinned slowly.
“Sure.”
Annabeth appeared behind him, grey eyes flicking from Draco to Hermione to the slight space between them.
Understanding dawned instantly.
“Oh,” she said softly.
Draco stiffened almost imperceptibly.
Percy blinked. “Oh what?”
Annabeth’s smile was faint.
“This just got interesting.”
Hermione felt heat rise up her spine.
“This is not relevant to your quest.”
“Everything’s relevant,” Annabeth replied.
Percy looked between them again, thoughtful now rather than teasing.
“You’re hiding something,” he said simply.
Draco’s expression chilled.
“And you’re trespassing.”
Percy’s hand twitched near his sword.
Lightning flickered brighter above them.
The castle trembled faintly.
All four froze.
From somewhere deep beneath the stone foundations, something answered the storm.
A low hum vibrated through the tower floor.
Percy’s sea-green eyes sharpened.
“That’s it.”
Hermione felt it too now — ancient magic resonating beneath her feet, older than wandcraft, older than the Founders.
Draco’s hand brushed hers instinctively.
Hidden from Percy’s view.
She didn’t pull away.
The hum grew stronger.
Percy’s jaw tightened.
“It’s waking up.”
Far below, water in the Black Lake began to churn.
Nico stepped out of a patch of shadow near the doorway.
“It’s not just a weapon,” he said quietly.
Hermione turned.
“What is it?”
Nico’s dark eyes flicked toward the floor.
“It’s hungry.”
The castle groaned.
Lightning struck the lake at last.
And the storm refused to leave.
—