They swam to one side of the hatch first, staying out of the light that came through the glass walls of the reverse aquarium. It was an interesting though slightly distorted view, looking in through the side rather than from above.

When all looked clear, Alex signaled to Sky, and they went toward the sliding hatch door. Alex moved his hand up and down the side, looking for the button that would open it and let them into the small drainage room. Finally, fumbling along a side panel, he hit it. The door slid open. There was already water in the holding place, so instead of getting whooshed into the open space by a wall of water under extreme pressure, he and Sky merely swam into the box.

The outer door slid closed behind them, and the door in front of them opened. The water in their box rushed out and fell through a grate in the floor. Alex and Sky landed haphazardly on top of the grate. “Looks like there’s probably an art to this,” Sky said, laughing under her breath as she got to her feet.

Alex grinned, and all the reasons he liked Sky rushed through his mind along with a dull ache. He had to focus. “Okay,” he whispered. “No mistakes. Let’s get the stuff. Coast is clear.”

They each grabbed a suit and a helmet and rolled the suits up carefully so they wouldn’t get wet inside when they went back out. Sky pressed the button. The inner door opened to the now waterless holding space. They stepped in, and the door closed behind them. “Stand back and hang on,” Sky muttered. “Here comes a wall of water.”

She cringed and pressed the second door’s button, bracing herself. But this time the door opened very slowly, letting the water in at a manageable speed. “Very sciency,” Alex remarked as the water level reached his neck. “Here we go.”

They took deep breaths and held them. Once Sky and Alex were completely submerged and the water had reached the top of the box, the door opened all the way. They exited and swam the distance to the surface, eventually popping up out of the water directly in front of Lani and Henry, who had leaned over the edge of the island, trying to see.

“Here you go,” Alex said, flinging his helmet and suit up over the edge. Sky did the same. They hauled themselves up with a little help and stood before their friends, dripping. “Nice and easy,” Alex said. He took off his shirt, squeezed the water out of it, and put it back on. “No problems. Nobody saw us.”

Sky explained how the doors worked while Lani and Henry put on the suits.

“You guys okay? You know where you’re going?” Alex asked.

“Of course, you dolt,” Lani said.

He smiled. “Just . . . don’t get caught here, okay? Your dad will kill me if anything else happens to you.”

“We won’t. In fact, Henry calculated it, and he thinks we’ll be back in ten minutes or so—if we can find the right room for Copper.”

“That’s a big if,” Alex muttered. He was definitely nervous about Operation Copper working as planned. So many things could go wrong.

“Oh!” Sky said. She rummaged through her wet pocket and pulled out a thin gold chain bracelet. “Show her this so she’ll know it’s safe to go with you. She’ll recognize it.”

Lani took it and, since she couldn’t reach her pockets with the suit on, slipped it on her wrist. “Got it.”

“Let’s go,” Henry said, bouncing a bit.

Alex gave them both a quick embrace. “Best of luck, you two,” he said. “Be smart and be careful. You can do this.”

“We know,” Lani and Henry said together, both wearing smug smiles. And with that, the Haluki children dove into the sea.

Shiver Shake Volcano Quake

Alex, Sky, and Ms. Octavia climbed up the volcano to the skylight to get a glimpse of Lani and Henry. It didn’t take the sister and brother long to figure out the doors. Soon they were tumbling onto the grate. They shed their suits and helmets and hung them up on the pegs where they belonged. Then they set out in search of Sky and Crow’s mother, looking exactly like they belonged there.

Lani wore a purple shirt and gray pants. Henry wore a red shirt and black pants. If someone looked closely, they’d find a very odd-looking seam in Henry’s pants where several pieces of clothing had been sewn together to make it work, but it wasn’t visible at first glance—at least not from the skylight.

“They’re heading to the spiral staircase,” Alex relayed to Simber, who was resting his wings nearby. “They’re going down— Nope, false alarm. Lani’s stopping and looking at something inside a glass case next to the stairs. Henry’s keeping watch. What the heck— Okay, now he’s tugging at her to hurry up.” He laughed nervously under his breath. “It’s probably a bunch of books or something. She can’t resist them. Come on, Lani.” He paused, jiggling his foot. “Okay, finally. Now they’re going down.”

Simber growled. “Ten minutes. Surrre.”

A moment later, Alex looked up. “They’re out of sight.” He blew out a breath. “I hope they find her.” He was more worried than he’d let on before. Who knew what these pirates would do if they found two kids who didn’t seem to belong to anyone?

As they waited Alex fidgeted. He and Sky both shivered, having brought nothing dry to change into. After a while, Alex retrieved his robe from Simber and held it out to Sky. “Here,” he said gruffly.

She took it and thanked him just as tersely, though she wasn’t quite sure why. They sat back against some rocks, not talking, and watched the scene below.