Hermione had never felt so useless.

The stone floor beneath her knees was cold and rough, scraping her skin through her torn jeans. Her wrists were bound behind her with coarse rope, magically reinforced, and no matter how hard she twisted, fought, or cried, they held tight.

Above her, Harry screamed again.

The sound tore through her chest like glass. She squeezed her eyes shut, but it did nothing to stop it. The agony in his voice, raw and broken, was something she knew she would never forget.

"Stop!" she shrieked. "Please! Take me instead leave him alone!"

No response.

Only Bellatrix's laughter, high and lilting and utterly mad, echoed down from the top of the tower like a song sung to the moon.

Hermione turned her face upward, straining to see, but the platform above hid him from view. She could only hear the clink of the chains, the faint rustle of movement and Harry's pained breathing when he wasn't crying out.

Her stomach turned. She felt like she might be sick.

Tears blurred her vision, but she didn't care. "Harry please hold on," she whispered, voice shaking. "I'm here. I'm trying. I swear, I'll get us out of this…"

A Death Eater loomed nearby thick-set and silent, wand in hand, watching her like a hawk. They hadn't spoken since dragging her in, hadn't even laughed like Bellatrix. It was worse, somehow. Colder.

Hermione's mind raced. Spells. Wandless magic. A distraction. Anything.

She pressed her fingers against the floor behind her, subtly tracing the stone. She could still feel the residual warmth of the charm she had tried to send earlier. A flare of hope flickered. Had it reached anyone?

Another scream from above shattered the thought.

Her whole body recoiled at the sound Harry's voice cracked halfway through, raw from overuse. He sounded close to losing consciousness.

No. She couldn't let him die up there. Not alone. Not like this.

She sucked in a breath and shouted again, voice breaking: "Stop hurting him, Bellatrix! You want pain? Then use me!"

Above, there was a pause. A moment of silence too long.

Then Bellatrix called down, sweetly: "Oh, Granger… don't worry. You'll get your turn."

Hermione's blood turned to ice.

Hermione's fingers trembled against the cold stone, but her mind sharpened with purpose. The fear was still there flooding her chest, her throat but beneath it, something deeper simmered.

Focus.

She forced her breathing to slow, eyes fluttering closed. She remembered what Professor Flitwick had once said, long ago in a moment she'd barely registered at the time: "Magic flows strongest when channeled through need, not want."

Well, she thought, her jaw tightening, I've never needed anything more than this.

Her hands curled subtly against the floor. The ropes around her wrists dug in painfully, but she pushed past it, grounding herself in the sensations the roughness of the floor, the coolness of the night air, the fire in her chest.

Lumos, she thought fiercely, not for light but for release.

For a moment, nothing.

Then

A spark.

It wasn't light, but heat. A rush of energy burst from her fingertips, faint and flickering, barely visible to the eye but enough to make the ropes twitch.

The Death Eater nearby turned slightly, suspicious. She held still, trembling from the effort.

Do it again, she told herself. Strong emotion. Channel it. Picture the ropes falling away.

She imagined Harry's face, pale and strained, hanging from the chains above her. She imagined Bellatrix's sick grin, and the sound of his scream, and the hopelessness of watching him suffer while she did nothing.

Her heart screamed as loud as her mind.

Finite incantatem.

The ropes twitched again then hissed, smoldering, smoking faintly

And snapped.

Hermione collapsed forward with the sudden freedom, gasping. She caught herself on her hands, then immediately rolled into the shadows behind a broken column, heart pounding in her ears.

The Death Eater spun at the noise. "What?"

Hermione didn't give him time to react.

She raised her hand not her wand, just her hand and snarled, "Expulso!"

The raw force of the spell blasted the ground beside the man's feet. The shockwave sent him stumbling backward, crashing into the wall with a grunt of pain and surprise. Dust exploded into the air.

Hermione scrambled to her feet, fingers outstretched and crackling faintly with magic she didn't fully understand but she didn't care.

Above her, the sound of chains rattled. Another scream. Harry.

I'm coming, she thought. Hold on, just a little longer.

Everything hurt.

Pain had settled into every inch of Harry's body like a second skin hot, pulsing, inescapable. His arms were stretched high above his head, wrists raw and aching from the chains, his legs barely holding him up anymore. Blood trickled from his temple, his side, somewhere beneath his shirt he couldn't quite place.

His vision blurred, flickering in and out of blackness. The air was too thin. He could hear his own heart pounding somewhere between his ears.

And still she was talking.

Bellatrix paced in slow, lazy circles, voice laced with venom and amusement. He couldn't make out all the words now. They slithered past his consciousness like smoke, fragments of threat and madness, promises of what she'd do to Hermione when she was done with him.

That thought alone that Hermione was below, listening was the only thing keeping him from collapsing completely.

Then something changed.

A tremor in the floor beneath him. A low, distant crack.

Bellatrix faltered mid-sentence.

Harry blinked, lifting his head with tremendous effort. His mouth was dry. "What… was that?"

Bellatrix turned, eyes narrowing as she looked toward the edge of the tower. "Nothing," she muttered, but there was a flicker of uncertainty in her expression now. "Stay awake, Potter. You don't get to pass out just yet."

But he had felt it.

A ripple of energy raw and uncontrolled rising from below like heat off sunbaked stone. Not Death Eater magic. Not dark.

Something brighter.

Something familiar.

Hermione.

His lips twitched. It wasn't quite a smile too pained for that but something close. A spark of hope in the haze.

Bellatrix raised her wand again.

Harry met her eyes.

"You're going to lose," he rasped, the words a whisper, broken but firm.

Bellatrix sneered. "Bravado doesn't suit you, darling."

But even as she said it, there was another thud from below louder this time and a shout in Hermione's voice, fierce and defiant.

Harry's heart surged.

She was coming.

Hermione's lungs burned as she bolted up the spiraling staircase, her bare feet slapping against cold stone. Each step felt steeper than the last, her magic still crackling faintly in her veins, raw and unstable from her earlier spell.

But she didn't stop.

Couldn't stop.

Harry needs me.

She clutched the stolen wand in her hand the Death Eater she'd stunned below had dropped it in his fall, and it pulsed now with unfamiliar energy. It wasn't hers, but it would have to do.

Another scream echoed from above.

She nearly stumbled, fingers tightening around the railing. "Hold on, Harry," she whispered under her breath. "I'm coming, I'm coming"

At the top of the stairs, a blast of red light tore past her head.

She ducked instinctively, flinging herself to the side as a second Death Eater this one stationed at the tower's threshold advanced with a cruel smile.

"No further, Mudblood," he sneered, wand raised.

But Hermione was faster.

"Petrificus Totalus!"

The spell hit him square in the chest, and he went rigid, collapsing backward with a heavy thud that shook the narrow floor. She didn't even look down as she stepped over him, sprinting toward the open arch that led to the Astronomy Tower's platform.

Wind slammed into her as she burst into the moonlight.

What she saw made her blood run cold.

Harry, hanging from chains, barely conscious his body limp, bloodied, his eyes fluttering. Bellatrix standing before him, wand raised, her expression gleeful and cruel.

"Get away from him!" Hermione screamed.

Bellatrix turned, eyes narrowing. "Oh, you're faster than I thought."

Her wand swung toward Hermione.

Hermione didn't hesitate.

"Protego Maxima!" she shouted, throwing her full will behind it.

A shimmering wall of light erupted in front of her, catching Bellatrix's curse and shattering it midair with a crack of thunder. The blowback sent Bellatrix stumbling.

Hermione charged forward.

"Expelliarmus!" she roared.

Bellatrix's wand flew from her hand, clattering across the stone.

For one breathless moment, they stared at each other Hermione shaking with fury, Bellatrix wide-eyed and smiling in that mad, delighted way that made her skin crawl.

And then Bellatrix laughed. "Oh… you're fun."

Hermione didn't answer. She rushed to Harry, her hands trembling as she reached up toward the chains.

"Harry," she whispered. "It's me. I'm here."

His eyes fluttered, a faint sound escaping his throat a breath, a name, or maybe just relief.

Hermione pointed the wand at the shackles. "Alohomora."

They didn't budge.

She clenched her teeth, tried again. "Finite Incantatem!"

The chains loosened just barely.

Harry sagged.

She caught him, barely managing to lower him to the ground without letting him collapse. Her hands touched his shoulders, his face, panic rising at how cold he felt.

"I've got you," she murmured. "You're safe now. I've got you."

But behind her, Bellatrix's laughter still echoed on the wind.