A bit clumsily.

She moved, deeper into the passage, away from the tapestry entrance. The voices were right there on the other side of the fabric, distant enough to make out words.

"...should check the passageway behind the tapestry..."

"...supposed to be one around here somewhere..."

"Which tapestry was it?"

Hermione went faster.

The passage was narrow and dim, torches mounted at long intervals on the walls, pools of light with stretches of shadow between them. She ran through the shadows and into the light and back into shadow, one hand trailing the wall for guidance, both hands free in the enclosed space — no one here to see her, no covering needed.
The passage curved to the right and she followed it, and the curve became an incline, gradual at first then steeper, and she felt something loosen slightly in her chest.

Going up. It's going up.

That was something. That was more than something.
She ran.

The passage seemed to go on longer than any passage had a right to, just stone and shadow and the steady upward curve, and then her right foot hit something solid and the pain exploded through her toe — sharp, immediate, intense — and she stumbled forward, hands shooting out to catch herself against the walls before she went down completely.

She stood there for a moment, gasping, the pain radiating up through her foot.

"Ow," she whispered. "Damn it."

She looked down.

A step. The first step of a staircase, leading upward into the dimness.

The pain was already receding behind the significance of what she was looking at. Stairs. Going up. This passage went somewhere, led upward, and if she was lucky — if for once tonight she was actually lucky — it led where she needed to go.

Don't stop. Keep going.

Hermione began climbing, moving quickly despite the throbbing toe. The stairs spiraled upward, walls close on either side, torches providing just enough light to see each step clearly. She climbed steadily, hope building with each foot of altitude gained.

She wasn't far up — a dozen steps, perhaps — when she felt it.

The step beneath her foot gave slightly. A subtle depression, a wrongness that registered in her body before her mind could name it.

No, wait—

The stairs transformed beneath her. The individual steps melded together, losing their edges, becoming one smooth continuous surface.
A slide.
She was already mid-step, already committed, weight forward, and her footing simply disappeared.

Hermione fell forward onto the slide and the breath knocked out of her on impact — cold, unyielding stone pressing hard against her front, her breasts compressed flat against the surface.
And then gravity took over and she was moving, sliding backward, feet first, the polished stone carrying her back down with gathering speed.

The trick step.

The shortcut had a trick step. She'd known that.
She'd known that and she'd been running in the dark and she simply hadn't thought and now—

Her hands stretched out over her head, scrabbling against the smooth stone, finding nothing to grip.
The surface was too slick, too polished. She picked up speed. The stone pressed against her breasts with the friction of descent, an uncomfortable grinding pressure that would leave them tender. She couldn't stop. She couldn't do anything except go where the slide took her.

It took her all the way to the bottom.

She came to rest on the flat stone at the base of the stairwell, sprawled on her stomach, completely still.

For a moment she simply lay there.
Breathing.
The slide had reset behind her — she could hear the faint magical sound of the steps reconstituting themselves, each one clicking back into place in the silence of the passage. Her breasts ached where they'd been pressed hard against the stone. Her toe throbbed. She was naked and wet and lying face-down on a cold floor in a hidden passage somewhere in the walls of Hogwarts, and she had just slid down a trick staircase like a child on a playground.

She pressed her forehead against the stone.

Of all the—

She slammed her hand flat against the floor once, sharp, and let the anger move through her and out of her. Then she lay still again.

Get up, she told herself. It reset. Try again. This time watch for it.

She'd survived everything else tonight. She could survive a bruised chest and a wounded ego. Just had to be smarter about it.

Hermione pushed herself up, got to her feet, and stood for a moment with her hands braced on the lowest step, studying the staircase above her.
The steps were back to normal — individual, distinct, innocent-looking. She counted up from the bottom.

Eight steps. Nine. Ten. Thereabouts.
That was where it had given way.

Don't step on it. Step over it.

She climbed carefully this time. One hand on the wall. Watching each step.
Counting.

Eight.
Nine.

She stopped.
The step in front of her looked identical to every other step.
But she knew.
She lifted her leg high — higher than necessary, an exaggerated step that would have looked ridiculous — and brought her foot down firmly on the step above it.

Solid stone.
No give.
No transformation.

She breathed.

Finally.

She kept climbing, past the trick step and beyond, and the staircase stayed solid beneath her feet all the way to the top.
The landing appeared ahead through the dimness, and beyond it a door — actual wood, actual iron fittings, the outline of it visible in the faint torchlight.

Hermione stood at the landing and looked at it.

Whatever was on the other side, she was about to find out.

(Note: This chapter was beta’d by user qwertpoint.)