“I can send a wave to throw all of you on shore,” Luce announced. She tried to sound cold and determined. “Let me go now, and I won’t have to hurt you.” A few mermaids stopped where they were, gaping in sudden doubt, but Jenna gave a piercing cry and leaped.

Luce didn’t have a chance to gather her breath or to think about what she should do. Instead the music that burst from her was shrill and spontaneous and uncontrolled, yanking a vertical pillar of water straight up under Jenna. Jenna suddenly flailed at the peak of a steep-sided wave ten feet high, towering in the tightly confined space of the cave, and then Luce realized with dismay that the wave was about to throw Jenna far onshore. Luce barely mastered her voice in time to send the wave swinging sideways, slamming Jenna against a rocky outcropping instead. Jenna howled in shock from the impact and then dropped into the water, stunned and keening. Dozens of voices were jabbering, and tails flashed randomly through the cave’s continual dusk.

Luce dove. She might have hurt Jenna seriously, maybe even broken some bones, but there was no time to think about that. Luce whipped her way back out of the cave and angled toward the surface at the sight of wavering fins. Violet was there, a feverish glow in her eyes, her smile somehow sad and eager at the same time. And the distant, windy voice still beckoned them, though now it was so faint Luce’s heart burned with desperation at the hopelessness of reaching it in time.

Violet’s head dipped toward the water. It took Luce a moment to understand that Violet was bowing to her.

“Queen Luce,” Violet whispered, “you saved me before. I know you’ll save her, too!” Luce felt the handle of the knife pressing into her hand and tried to focus. She could just see the fishing trawler, a rusty dot propped in front of the dim blue shelf of Russia far away. In the instant before she dove, it occurred to Luce that the ship was farther from the safety of the coast than she had ever swum before.