For the next length of time, they watched the fiery lava sputter and hiss in the water as Captain Ahab brought them a bit closer to the island. When the volcano stopped steaming and it appeared safe to go ashore, the team disembarked. This time, knowing there would be warning tremors when the island was about to sink, Alex ordered small groups to the other skylights they’d found, and he assigned Sky, Crow, and Carina each with a different group so they’d have a better chance of spotting Copper.

Just as dusk was falling, a shout rang out. Sky, Fox, Ms. Octavia, and Alex scrambled to their feet. A second later, Simber came soaring toward them and landed. They hopped onto his back as he explained.

“Crrrow spotted herrr,” he said. “She hasn’t noticed them yet.”

Sky nearly leaped from Simber’s back as he was still attempting to land. She joined her brother. “Where?” she demanded.

“There, with the brown dress. She’s carrying a bucket and a mop. See?”

Sky strained against the daylight just as the interior lights of the underwater island began to turn on. “I see her!” she cried. “Oh, that’s her, all right.” She rubbed Crow’s back. “She’s alive! Good job, Crow. We can’t let her out of our sight.”

Octavia and Fox took a good look at the woman. “We’ll head back to our skylight,” Octavia said, “so we can watch if she visits that side of the island.”

“Sim, will you take me to the third skylight?” Alex asked. “I can recognize her now.”

Simber nodded brusquely and Alex climbed on. They traveled to the third spot in silence.

Alex slid off and joined the small group that huddled there, filling them in on what was happening. “Have the squirrelicorns come out here,” he said to Simber, “and post them two per skylight so they can spread the word if we have to act fast. And they can help get us back to the ship if the island sinks.”

Soon six squirrelicorns could be seen circling their posts, while everyone else remained still and on the watch for Copper.

From time to time, when there were few pirates moving about, Alex’s glance moved to the distant glass cage where the sea creatures were kept. Florence lay in the same position as before, unmoving. Alex’s gut twisted.

As the evening progressed, colorfully dressed pirates emerged through the set of large doors on the upper floor and mingled with each other, leaning over the sides of the walkway and looking out at the sea creatures in the glass cage. Or they appeared briefly, barking out orders to other, younger pirates or to the few in drab brown clothing like Copper. Not one of them looked up at the skylights, but the Artiméans were also careful not to attract any attention.

Although Lani gasped once, and nearly fell onto the glass when she was observing two pirates talking to one another as they unrolled a scroll and studied it.

“What is it?” Samheed asked. “Did something happen?”

Lani stared at the scene below. “That scroll—those two pirates are looking at it. The drawing on it looks . . . interesting. Like maybe I’ve seen something like it before.”

“Oh, brother,” Samheed said. “You’re supposed to be watching Copper, remember?”

Lani scowled and didn’t respond. She strained her eyes to get a better look, but just then one of the pirates glanced around, so she had to duck to keep from being seen. When she dared to look again, they had gone down to the lower floor. They opened a glass display case near the stairs, unrolled the scroll, and pinned it inside. Then they closed the case once more and looked down into it at their drawing.

“What are they doing?” she whispered.

Samheed turned to look at her. “Will you focus, please?”

Lani felt like arguing—she was definitely focused. But not on Copper. Reluctantly she held her tongue. “I guess it was nothing,” she said.

Copper stayed in view below, scrubbing the wood-plank walkway near a young man who was washing the glass walls. For the most part, the pirates ignored them.

Eventually the top level of the underwater island quieted, and more people made their way down the stairs. On the lower floor, they went individually through smaller doors.

“It looks like the upper floor is where some of them work, and the lower floor is where they live,” Alex noted. “Plus, there’s a stairway that goes down another flight.” He couldn’t see anything down there.

Soon Copper stood up straight and stretched, wiping her forehead with her sleeve. She signaled to the window washer, using Warbleran sign language.

“Do you think he’s from Warbler too?” Ms. Octavia asked.

“Yes,” said Fox. “I’m sure of it.”

Alex couldn’t help but glance at Simber to see the cat’s reaction, but when Simber did the same to Alex, both quickly looked away. Alex frowned and concentrated on Copper and the man below.

The man nodded. The two of them packed up their cleaning supplies and made their way down a sweeping spiral staircase to the terrarium floor, where the pirates had gone. But Copper and the man kept going down the stairs to the floor below that. Soon their heads disappeared from sight.

When Alex heard a sound behind him, he looked up. It was Sky and Lani.

“Alex,” Lani said, “we need a meeting. You, me, Henry, Sky, and Ms. Octavia. Sky has an idea.”

Sky’s Plan

I noticed something interesting about the pirates,” Lani began. “Henry noticed it too. They look like us.”