The train chugged along the Scottish countryside, its steady rhythm lulling Harry Potter toward sleep. But the peaceful afternoon had vanished.
The wind picked up without warning. Trees in the distance bent low as if some giant hand pressed down on their crowns. Nearby grass rippled in waves, flashing pale undersides like ripples on water.
Clouds sank lower, scraping the hilltops. Their color darkened from pale gray to lead, then to deep black, piling up like they might collapse at any moment.
Daylight drained away inch by inch, as if night had decided to arrive early. Inside the carriage, the lamps flickered on, turning the windows into hazy mirrors.
A single raindrop streaked crookedly down the glass. Then another, and another. Soon a fine net of rain covered everything, weaving a shifting veil of mist outside.
The train jolted and slowed to a stop with a heavy clunk.
Harry snapped awake. "It's already dark? Are we there?"
"It's just rain," Hermione said, frowning. "We shouldn't be at the station yet. Why did we stop?"
Harry stared out the window, face pale, fingers gripping the seat hard. Something terrible was coming—he could feel it.
"What's wrong, Harry?" Hermione asked.
"Outside… there's something out there," Harry whispered. "Don't you feel how cold it suddenly got?"
He was right. The temperature in the compartment dropped fast. Frost crept across the glass—not ordinary cold, but the bone-deep, soul-freezing kind that made your chest ache.
Ron pressed his face to the window, too scared to open it. Outside was pitch black. Nothing visible, only the freezing air pressing closer. His hand felt like it might stick to the glass.
The hooded man who'd been sleeping since they boarded pulled his ragged cloak tighter around himself but didn't wake.
The carriage lights flickered and dimmed with a low buzz.
A few young witches and wizards in the compartment stared nervously at the transparent sliding door.
"It's coming," Ron muttered.
Before the words left his mouth, the door slid open by itself.
A hunched, floating figure hovered in the doorway, draped in a tattered black cloak. The hood hid its face—but what little showed wasn't human. It was something hollow. Something that fed on everything good.
A wave of emptiness and despair rolled into the compartment.
The dark shape swept its gaze across them, then leaned forward, head tilting straight toward Harry Potter.
"Harry… Potter…" A rasping, hollow voice hissed from under the hood—maybe calling his name, maybe just mindless hunger.
Harry let out a choked groan and doubled over. His glasses slid down his nose. His green eyes widened in terror as he saw a round, sucking mouth-like shape coming toward him. All the warmth, all the hope inside him was being drained away. In his ears, a woman's scream echoed—high, desperate, familiar.
"No—!" Ron tried to stand, but a crushing wave of despair slammed into him. His body locked up; he couldn't even reach for his wand.
Hermione wasn't much better. A scream died in her throat. Her books scattered across the floor, but she couldn't move to pick them up.
"Expecto Patronum!"
The hooded man who had been sleeping suddenly stood. In one smooth motion he drew his wand and cast the spell.
His voice wasn't loud, his movement wasn't dramatic. But a powerful wave of silver light burst from his wand tip like a rushing river, slamming straight into the Dementor's hooded face and body.
The creature let out a silent screech—too high for human ears—and recoiled. The edges of its cloak shrank back like spilled ink being sucked up.
The same scene played out in the next compartment.
The moment the train stopped, Julien's silver lime wand was already in his hand. The familiar warmth of the wood pushed back some of the creeping chill.
Seeing him move, Elizabeth and Liriya drew their wands without hesitation.
Daphne and Astoria Greengrass watched in surprise at how perfectly in sync the three of them were.
"It's coming," Elizabeth said quietly.
Right on cue, Liriya pressed her hand to the floor and whispered a short chant. A band of green thorny vines shot up, blocking the compartment door.
"Won't work," Julien warned. "It's a Dementor."
"A Dementor?!" Daphne's voice shook with disbelief. As a pure-blood from an old family, she knew exactly what that meant.
The door slid open on its own. A rotting, tattered Dementor drifted in.
Everyone except Julien froze in terror.
The creature floated closer. Liriya's vines passed right through it with no effect. It ignored the others and drifted straight toward little Astoria, who was huddled in her sister's arms.
Astoria's small face had gone deathly white, lips turning blue. Even pressed against Daphne she looked freezing cold.
The black hood lowered toward her face.
Julien stepped forward in one quick stride, putting himself between the Dementor and Astoria.
"Expecto Patronum!"
A burst of silver-white light exploded from his wand tip. At first it was shapeless—fuzzy, flowing, like a swirling nebula still forming.
Then, in the heart of the light, a shape began to emerge: a sharp beak, spreading wings, something between a raven and an older, more ancient creature.
A raven. The symbol of Ravenclaw. Pyxis Black's Animagus form.
Julien's magic wasn't as strong as the man in the next compartment, so the silver light didn't strike the Dementor head-on. Instead it flowed around it—an ancient, almost ritualistic banishment.
The Dementor recoiled with a silent screech. Its empty hood gave a hollow wail, and it was pushed back out of the compartment, fleeing down the corridor.
The cold began to lift.