She leaned against Dr. Neill's side. He hit some computer keys, but he mainly just seemed to be watching for Nanny the old-fashioned way—staring at the water's surface. A few seagulls flew low over the waves.

“I miss Mommy,” Rose said suddenly.

“I miss her too, Rose.”

“Is she coming soon?”

“She's looking after her grandmother right now. I'm sure she'll call us as soon as she makes sure everything is okay.”

Rose nodded. If a person was sick, there was no one better in the world for looking after them than Rose's mother. Rose had been born with four defects in her heart. She had been a blue baby—her skin had actually turned indigo, her mother had told her—from not getting enough oxygen. It was why she hadn't grown as much as other kids her age, and why her fingertips were spatulate, clubbed.

Rose looked down at Dr. Neill's arm. Not his real one, but his prosthesis. It fit in his sleeve, but his fake hand was odd and clublike compared to a normal hand. The kids in Cape Hawk had whispered things their parents had told them—that when Dr. Neill was a boy, right after the shark had attacked him and his brother, killing Connor and ripping his arm off, he had had a hook.

The kids had called him Captain Hook, and the name had stuck. Rose couldn't bear to think of people teasing him. Rose loved him. Her mother had told her the story of how Dr. Neill had been her first friend in Cape Hawk. He had stopped by her cabin one day. Rose loved to picture this: the house deep in the woods, with no one around, and Dr. Neill heard noises coming from inside, and that was because Rose was being born. He had brought Rose into the world. . . .

“Why do you look so worried?” she asked, watching him gaze out over the water.

“I'm not worried,” he said. “I'm just wondering about those menhaden—minnows.”

“Do they have something to do with Nanny?”

“They could,” he said, typing something into his computer, bringing up a whole new screen. It showed some graphs of currents and water temperatures. Rose watched him type in “Narragansett, Rhode Island,” and the screen changed yet again. Outside, the seagulls screeched and started diving. Rose heard some kids shout, and she saw them pointing at the water.

Dr. Neill grabbed her hand instantly. The kids were yelling, pointing at the surf. Dr. Neill gave her a look, and then he and Rose hurried across the yard.

Two boys had run all the way to the end of the rock breakwater that stuck out from the narrow, pebbly beach. They were calling to their friend, who was tearing along the seawall with a fishing rod in one hand and a net in the other.

“What are you fishing for?” Dr. Neill asked the young boy.

“Fins, man!” he called over his shoulder.