Read Chapter 17: The Hidden Diamond

The crypt door groaned open, and the smell of wet stone and old salt rolled out to meet them. Isabelle clicked on her torch, sweeping the beam across the flagged floor. The space was small—no grand vault, just a low-ceilinged chamber beneath the chapel wing, its walls rough-cut and sweating with damp.

“It doesn’t match the main foundations,” she said, kneeling to run her hand along the base of the wall. “The original castle was here. This is the part my grandmother’s diaries called the heart of Keravel.”

Yann hung back by the door, lantern raised. “You’re looking for something hollow.”

“I’m looking for something that was never meant to be found.” She worked her way along the wall, tapping the stones one by one. Granite gave back a dull, dead sound. Granite gave back the same. She was nearly at the far corner when her knuckles met a stone that rang—a note too clear, too musical.

“Here.”

She scraped at the mortar with the edge of her torch. It crumbled like dried clay. The block shifted, then slid inward with a grating sigh, revealing a cavity black as ink. Isabelle’s breath caught. She reached in, fingers brushing cold iron, then something smooth and weightless.

She pulled it out.

It was a statue, no taller than her forearm—a woman in flowing robes, her face worn smooth by centuries of sea air. But her hands, clasped at her breast, held something that caught the torchlight and broke it into a dozen scattered stars.

A diamond. Cut in the rough shape of a heart, flawless, burning with a cold inner fire that seemed to drink the darkness.

“The Heart of Light,” Yann whispered.

Isabelle turned the statue over. There was no maker’s mark, only a single word scratched into the base: *Avel*.

The moment her fingers closed around the diamond, the world dropped away.

She was no longer in the crypt. She stood on a cliff at dusk, the sky burned green and gold. Before her, Maëlle—younger than she’d seemed in the phantom ship, hair wild in the wind, eyes bright with feverish hope—knelt at a stone altar. The sea clawed at the rocks beneath her, and a voice rose from the depths, a sound like grinding ice and whale-song made thunderous.

*Ave…el.*

Maëlle raised the diamond. “I pledge my line, my blood, my name. In return, spare him. Spare my husband’s ship upon the waters. Let the Marchand name pass safe beneath your moon.”

The sea answered. A hand of dark water rose from the troughs, impossibly shaped, fingers of spray and salt. It reached toward the diamond—

And paused.

A hiss, like steam on a hot stone. The water recoiled. *Not enough. A gem for a life is no exchange. You would barter the weight of your whole bloodline for one man? Then let your bloodline pay the price it cost you.*

Maëlle screamed as the wave swept her from the cliff. Isabelle felt the cold clamp of the sea around her own throat, the horrid weight of bargain sealed wrong—

And then she was back in the crypt, gasping, the diamond still clutched in her fist.

“Isabelle.” Yann’s hand was on her shoulder, his face tight with fear. “You went white. You weren’t breathing.”

She looked down at the stone. It was warm now—not with the curse’s cold, but with something older. A pulse that beat against her palm like a second heart.

“I saw it,” she said. “The ritual. Maëlle offered it to Avel, but he refused because she asked him to spare one life in exchange for a gem. It was never about the stone. He wanted blood. He wanted *her*.”

“And she gave him the next best thing.” Yann’s voice was flat. “Her whole line.”

“Yes.” Isabelle’s throat tightened. “But the vision showed more. The way to break it—you don’t return the diamond and walk away. You offer it freely, with an equal cost. A life’s worth of weight, willingly surrendered. Not a hostage. Not a victim. An equal exchange.”

Yann’s face hardened. He knew what she was about to say.

“Don’t.”

“If I descend to the gate and offer the diamond as Maëlle did, but without asking for anything—if I give it as a free gift, something precious freely surrendered, with no plea attached—” Isabelle’s voice shook. “The curse has to accept. It has to see the bargain completed true.”

“You’ll die.”

“Maëlle’s mistake was trying to trade another’s safety for treasure. If I offer everything—the diamond, my own blood, freely—the magic will have its exchange. It won’t need the rest of my line. It will close the circle with me.”

“Isabelle.” He stepped closer, jaw tight, hand gripping her arm like he meant to keep her on land forever. “You said you wouldn’t do this alone. You said you’d let me descend with you.”

“With, not instead. I never said I would let you take my place.” She met his eyes. “I can’t let you offer yourself, Yann. You’re not Marchand blood. The curse has no hold on you. My life is the only coin it will accept.”

He stared at her, the lantern flickering low, painting shadows across his face. “Then I’ll be beside you when you do. Whatever happens. I won’t watch you go alone down there, Isabelle. You saw what’s in that water.”

She opened her mouth to argue—but the diamond pulsed in her hand, a thrum of warning that vibrated through her bones. From somewhere deep beneath the castle, below crypt and foundation and rock, a low and terrible sound rose through the floor. A woman’s laugh, unbodied, curling like smoke up the stairwell.

The locket around her neck went so cold it burned.

Yann’s lantern flickered. He stepped in front of her, raising the light toward the crypt door, where—

Nothing. The empty archway. The laugh faded into the sound of the sea.

Isabelle looked down. The diamond was dark now, its fire dimmed to the faintest pulse beneath her thumb. She could still feel the vision’s shape inside her: the ritual at the underwater gate, the words she would have to speak, the moment she would have to let the water take her if the sea god demanded no less than blood.

She knew now what she had to do.

She also knew the curse was listening.