“What are you doing?” I breathed, and I didn’t have to pretend the bewilderment in my voice.

His head snapped up. “Nyx,” he said, blinking hard. His pupils were hugely dilated. “While you were gone, I started . . . What the Kindly Ones said through you. They said, ‘The name of the light is in the darkness.’ I swore to your mother’s grave that I would try. So I stayed up all night. Almost in darkness. And I almost, I almost remember the voice.” His voice was a wandering, lost thing. “There’s a way to save us. If I can just remember.”

I felt like a cobweb strung across the doorway, trembling in the draft and about to tear if I moved. If I had just waited one more day, tried one ounce harder in all the days before, maybe he would have dared the darkness and already remembered. Maybe he would have found a way to save us all. But now I was oath bound to destroy him.

Maybe he would have just remembered that there was no way to save Arcadia but his destruction. Whatever the truth, it didn’t matter anymore.

He stood, swaying slightly, and then he finally noticed Shade standing behind me.

“What—” he started, but his voice had torn me free. I was across the room in two strides and then I stopped his mouth with a kiss. I locked my arms around him; I felt his shoulder blades and the slight ridge of his spine, and the solid reality of what I was about to destroy nearly undid me.

But if I didn’t destroy him, the last prince would never be whole again. Nobody would save Arcadia. And I had sworn an oath to my sister.

“I’m sorry,” I whispered, and he went still beneath my hands as if he knew. Then I said loudly, “Break his power,” as I opened my hand.

The Children of Typhon rushed out between my fingers. I clung to him—to hold him down or share his fate, I wasn’t sure—but the shadows slid between our bodies, icy cold, as they wrapped around him. Then they began to drag him away. My grip broke; I scrabbled for purchase and managed for one moment to grasp his wrist—and his hand clutched my wrist in return, his eyes wide with fear—then they ripped him away and slammed him against the wall. My legs gave way, and I collapsed to the floor. It was several heartbeats before I could gather enough strength to look up.

The shadows held Ignifex against the wall; they writhed and clawed at him with a thousand tiny fingers. His whole left side was gone, the ragged edge not bleeding but shredded into mist.

Impossibly, he was still alive. And he smiled the wild, vicious smile that had made me fall in love.

“One half of power for one half of your knowledge,” he said to Shade. “Not such a bad bargain. At least now I understand why you coveted my wives.” He held out his remaining hand. “Take my hand. End this. And all my wives will be yours.”

As Shade stepped forward, left hand reaching, his right side melted into the air. He was smiling exactly the same smile.

“Wait,” I said, trying to stand, because this wasn’t right. I was still dazed, but I could tell that something was wrong. Shade was supposed to regain what had been stolen from him. He wasn’t supposed to lose one half of his body. He wasn’t supposed to gain my husband’s smile.

Their hands touched, fingertip to fingertip, and every candle in the room flared up. Then their fingers locked down to clasp their hands together. Light exploded through the room.

And I remembered the last vision that Shade had shown me in the Heart of Fire, the vision that had broken my heart until I forgot it again.

Once more I saw the hallway of the ancient palace, but this time it was night. One lamp burned on the wall, and in that flickering light I saw the last prince fall to his knees before the box.

“O Kindly Ones,” he gritted out. “O Gentle Folk of Air and Blood. O Lords of Tricks and Justice. Come to my aid.”

The silence stretched on and on, broken only by his ragged breathing, but he waited. Until a breeze swirled through the hallway, ruffling his hair and whispering against the stones, and on the breeze floated a thousand pinpricks of light, and the light was laughing.

Then the lights clustered, coalesced, and formed into the shape of a woman. Her hair was made of moonlight, her eyes of fire; she was lovely and terrible as a lightning bolt.

“So you are the latest heir of Claudius,” she said. “Do you appreciate the gift we granted to your family? The wondrous protection granted to any worthy king?”

He stood proudly and faced her, his mouth set in a grim line.

“But you aren’t a worthy prince, are you?” She stroked one finger down the side of his face. “Is that why you called me?”

He let out a deep breath, the pride melting from his face, and then he said softly, “Please. Take the hatred out of my heart. I’ll pay any price, so long as Arcadia stays safe and I don’t have to end up alone in that box.”

The lady smiled and cupped his chin. “Of course,” she said. “Are we not the givers of gifts? You shall open the box tonight but not end up alone in it, and all the days of your life, you shall rule an Arcadia that will never be invaded. Only know this: after tonight, you must never again open the box, or all the bargain shall be undone. Time itself will unwind back to this moment, and you shall be locked with the shadows forever, as if you had never called us.”

He nodded. “I won’t open it again. No matter what.”

“Then kiss me,” she said, “and the bargain is sealed.”

He kissed her quickly and fiercely. She laughed and said, “Open the box, my prince.”

Slowly, he stepped to the table, unlatched the box, and lifted the lid.

Shadows boiled out of the box: the ten thousand Children of Typhon. And they were singing:

Nine for the kings that ruled your house,

They are now betrayed, oh.

More and more and more streamed out, like an endless river of darkness; they skittered across the walls and pillars, leaving tiny claw marks, and their high little voices were a fistful of claws in my ears.

“No!” the prince shouted, but the lady caught him by the shoulders and held him.

“This is your wish, my prince. We must fulfill it.”

He fought against her, but she was unmovable. And she held him as screams echoed throughout the castle, as the floor and pillars shook, as flames appeared at the end of the hallway. Stones fell from the ceiling about them, shattering the marble floor. One pillar crashed to the ground and then another.

Earlier he had screamed and struggled. Now the prince knelt quietly, his eyes wide and unseeing as his castle fell around him. Suddenly there was a great roar that just as suddenly cut off, as if the silence were a wall that had dropped down, and I knew that Arcadia was now inside the box, and the parchment sky curved over the land.