“The Renalt,” Ambrosine said. “That stubborn bitch. You’d think she’d have given up when we destroyed most of her warships.”

There was another boom and the ground beneath them shook.

“Perhaps we should go, mistress,” one of the Misarros suggested. Ambrosine silenced her with a look. Then she turned to Wyllin.

“This is your island,” she said. “I see it now. What is your price? What do you want? I will give you anything you ask for. You met my ancestor. We have a connection, you and I. I swear to wield this power only for good.”

The lie was so obvious it was almost sad. Wyllin looked at Ambrosine for a long moment, her eyes clear as dawn, revealing nothing. At last, she said, “I will show you. But it will destroy you.”

Ambrosine’s lips curled. “I’d like to see it try.”

Wyllin sighed and waved a hand over the fountain. Ambrosine gasped. She must be able to see the tether, Leo realized with a start. But he couldn’t, and judging by the way Agnes was squinting, she couldn’t either. Wyllin’s words from before came back to him.

I am the tether and the tether is me.

Ambrosine’s eyes grew round and bright—a dark hunger crept across her face and spread throughout her body, making her back hunch and her hands curl like claws.

“Yes,” she hissed. “Yes, I see. I see it now. Oh, it’s beautiful. Magnificent. It’s . . .” She licked her lips. “It belongs to my family. It’s mine. Mine . . .”

One claw reached out and Leo realized what she was going to do a moment too late.

“No!” he cried instinctively, having no love for his grandmother yet not wanting to see what would happen once she touched the chain of Cerulean magic. But Ambrosine had already reached up, wrapping her hand around the tether that Leo could not see. For one endless second, nothing happened.

Then she let out a choked cry, and her whole body was illuminated in a silvery-blue light—it shone out through her eyes, from the tips of her fingers, from each strand of her hair. She began to scream, and the light poured from her mouth in a torrent of brilliance. One long, high-pitched wail that pierced Leo’s heart and rang over and over again in his ears. The light coming from inside Ambrosine grew brighter and brighter, until she was engulfed in it, until her body was a mere shadow, an outline, and then there was a flash like a solar flare and Leo had to shield his eyes against it.

When he looked again, all that was left of Ambrosine Byrne was bits of ash floating through the air.

“She would never have let it go,” Wyllin said. “She would never have let it be until she saw it. It was consuming her thoughts and so it consumed her.”