The Potions Mouse

Chapter 1

Author's Note: This was written for the Once Upon a Time fest in 2019. My fairytale was a Finnish tale called "The Forest Bride: The Story of a Little Mouse Who Was a Princess". Thanks to my alpha, ArtemisiA, for the encouragement. Thanks to my beta, dormiensa, for her time, insightful comments, and letting my comma splices slide.

~*~*~

The world ended in two speeds.

Slow. The jet of green light as it sizzled through the air. Its impact with Harry Potter's chest, the beam fracturing like water striking an oiled surface. Harry's fall, the collapse of ankles, knees, and hips that left his broken body at the center of Hogwarts' crumbling courtyard.

Fast. The order to capture or kill everyone who had fought against Voldemort. The fight, wizards and witches slinging insidious spells across the narrowing field. The carnage. The sounds, smells, and sights of dead and dying flesh.

Hermione Granger, as she sprinted into Hogwarts, away from what should have been the final battle.

Running had always been the plan. She, Harry, and Ron had discussed it at length during their Horcrux hunt, on sunny days when the likelihood of Harry's death seemed most remote. Harry had made them promise, and they had sketched out a contingency that contained enough room for hope.

Flee the battle and get somewhere safe. Regroup at Shell Cottage, providing Bill Weasley, the Secret Keeper, was alive. Assess the damage, heal the injured, and bury the dead. Tell everyone about the Horcruxes. Resume the search. Survive the fight.

She looked left, right, and went cold. Where was Ron?

They had stood side-by-side in the courtyard. Her hand still ached from her grip on his forearm, restraining and steadying. Harry had fallen, and she had jerked backwards, taking Ron with her. He'd resisted, a contrariness so expected she'd instinctively felt annoyed. She'd started running, and he'd been close behind. She'd heard his breathing. Or had that been her own?

Had he followed her at all?

Hermione stopped at an intersection and turned, catching her breath, trying to hear over her heartbeat and the distant screams. Footsteps pounded toward her. She took a step forward, heart lifting. If Ron were safe, she had a chance. They all did.

He had to be safe.

One set of footsteps became many, and three Death Eaters rounded the corner. Hermione's blood ran cold. She had time for one breath: a single, gasping exhale that sounded like go.

Six jets of light rocketed down the long hall. Hermione's three, cast in quick succession. Only her first Confundus hit. The leftmost Death Eater staggered, his curse gouging a molten crater into the stone floor. She lurched left, dodging the second curse, which went off like a bomb against the wall behind her. The third hit, punching the breath out of her.

Dizzy, nauseated, she pressed a hand to her side. No blood. Her chest ached as her lungs reinflated. She forced herself to run.

Ron's absence changed nothing. She had to assume that he was with his family and safe.

The Death Eaters changed nothing. She had made a promise to survive.

Get somewhere safe.

The Room of Requirement.

It was on the seventh floor; she was ground level.

The nearest staircase, if it hadn't shifted, was two halls down on the left.

Her speed relative to the Death Eaters': not ideal.

Her injuries compared to theirs: equally unfavorable.

The calculation was clear: they would catch her. She needed another option.

A House Common Room.

Slytherin's was on this side of the castle, but she couldn't count on them for help. Hufflepuff''s was second closest, but in the opposite direction. She could go the long way. Take the staircase up to the first floor, loop around the castle, and maybe lose her pursuers in the warren of classrooms and broom closets.

Down two halls, then left. Hermione stopped just before tumbling off the empty stone ledge. The staircase had shifted. She was trapped.

The Death Eaters' footsteps grew louder as Hermione cast around for an idea. To her right, an old tapestry hid a secret niche, discovered during her Prefect patrols and often used by amorous couples meeting after curfew. It was better than nothing. Maybe she could surprise them and give herself a strategic edge, however slight.

She flung the heavy fabric aside, using her wand to still it. She pressed herself against the stone wall.

"Help me, help me, help me..." she muttered, barely a whisper.

The Death Eaters stopped at the empty ledge.

"What'd ya think, Cleve? She go over?"

One kicked a piece of debris over the ledge; it echoed as it struck bottom.

"Long drop," said Cleve. "Don't see a body."

Nervous sweat slid down her back as she readjusted her grip on her wand. Was she going to kill these men? They were going to kill her, or worse. No one would blame her for it. It was war.

"She's still 'ere, then..." said the first.

Hermione pressed herself into the corner. She couldn't do it. She couldn't kill them. Harry was dead, and Ron was gone. It was two against one, and she was trapped. It would be better to disappear, better to hide...

"Help me, help me, help me, hide me..."

Her whispered chant changed with her mind, and the specific request was one Hogwarts could oblige.

A rapid, shifting pain took hold, her body held captive during the distinctive agony of transformation. But this wasn't the familiar burn of Polyjuice, a temporary rearrangement of familiar features. This was Polyjuice gone wrong, the fracturing, shrinking, resetting of bones into shapes that were far from human.

The walls around her soared skyward, the quarried stones taking on grotesque proportions. A cave-like entrance appeared in the corner, smelling of stale air and refuge. She darted into it.

Bright light filled the space outside the cave. Then, it exploded. The shockwave reverberated in her chest, and her ears rang as stone boulders slammed to the floor. She cringed, making herself small.

"Where is she?"

"Impossible."

"Maybe she jumped."

"Let's go. The Dark Lord..."

"Yeah, I know what 'e said. Molliare. After you."

The Death Eaters landed hard on the level below, the Cushioning Charm poorly cast. Only they began to run did Hermione venture from her sanctuary. She climbed over mountainous chunks of stone and mortar and picked her way past the tapestry, half-torn and badly singed. She crawled into the hallway, pausing when the earth shook: a gradual, bone-deep rumble of stone against stone as the missing staircase shifted back into place.

The Death Eaters were gone.

But then, so was she.

Hermione sat on her haunches and raised her furred arms. Paws tipped with sharp, hooked nails had replaced her hands. She swiped them over her head and felt large ears, an elongated nose, and whiskers. A new set of muscles tensed along her spine. Her long, hairless tail flicked behind her.

A sliver of logic broke through the numbness. Being turned into a mouse was better than being dead or captured. And it was her own fault. She had read Hogwarts: A History often enough to have realized her mistake. She should have known better.

After all, Hogwarts always gave help to those who asked for it.