I was glad of it. I didn’t want her anywhere near Maddy. Plus, I’d have more focus without her eyes on me, and since she and Luca were in a fight, I didn’t want her presence distracting him. Luca was still shooting unhappy glances in her direction, so I went to the sunny part of the boat and got my fish ID cards out of my dive bag. I gave them to Maddy, and she started showing him the animals we would most likely encounter. By the time we neared the site, he was deep into it, more relaxed.

We all began putting on our wet suits and doing our final gear checks. I supervised Luca as he set his dive computer. He did a good job, eyes on the screen and not his mother, but when we were done, he said, “Is she not coming with us?”

I shook my head. “She wants to go deep, is all. You have to stay above sixty feet until you do your advanced class, mister.”

His nostrils flared. “Sure,” he said, sounding just like her.

I understood his disappointment. This was supposed to be a family outing, and his mom had made it into a singles mingle. She was turning now to have Mark zip up her wet suit, giving him a coy smile over her shoulder.

We anchored near the bow of the freighter, and one by one all three Babbages giant-stepped expertly off into the water. Roux paused at the brink, her regulator in her hand.

“Hey, Madison,” she called. It was the first time she’d ever said Maddy’s name. “You want to come on the deep dive with us? Or stay in the kiddie pool?”

I could feel the little hairs on my arms trying to rise, even compressed by my wet suit. I would not send my girl out of sight, into the sea, with Roux. Not with Luca’s secrets likely locked up tight inside her.

“No, thanks,” Maddy said, hardly looking up. All her focus was on Luca.

Roux didn’t press. She put her regulator in, and then, with a step and a splash, she was gone. I felt instantly calmer.

“You ready?” I asked.

Luca nodded. He seemed more focused now, too, shuffling in his fins toward the back of the boat. I held my mask and regulator to steady them and giant-stepped in. The ocean caught me. It was in a beautiful mood, sloshing me gently as I followed the trail line out of the way. I turned back to watch Luca make a good entry. He’d remembered to inflate his BCD, and he bobbed to the surface, grinning around his regulator. He signaled Winslow that he was okay, then got out of the way for Maddy.

We stayed on the surface for a few minutes, doing Luca’s buoyancy and weight checks. He was light, and I had Winslow pass me another two pounds. It was part of his certification, but it also gave Roux and the Babbages time to follow the side of the wrecked ship down and away from where we would be diving.

We descended slowly, staying vertical, letting Luca get his bearings and equalize. Visibility was okay, about thirty feet, and I saw Luca’s eyes widen with excitement when he looked down between his fins and realized we were descending into a huge, weaving cloud of silvery, small baitfish. They parted for us like a curtain, and the bow of the English Freighter came into view. Luca’s bubbles stopped.

I touched his arm to get his attention, then waved my hand gently back and forth, the signal to breathe. I heard his Darth Vader inhale, and then his bubbles were streaming up again. Maddy came up on his other side and grabbed his hand, tugging at him, wanting to show him a pair of butterfly fish. They were shadowing each other, mated for life.

He checked his air gauge and then turned with her. Maddy played her light over a flashy little school of blue-and-yellow damselfish, making their colors brighten and shine. I followed, glad to see them sticking so close. This was my favorite place to be on earth, and yet I could not shake my unease. We were all in the water with a predator, much more dangerous than any bull shark.

Luca was doing a good job with his form and his buoyancy, though to stay in position he made little flaily kicks and hand waves, very common for new divers. He only blundered into the bottom once, churning up the silt. The salt in the water made him more buoyant than he had been in the pool, and he’d overcorrected. He inflated and got up without overcompensating, then got into a good horizontal position, Maddy’s hand steadying him.

Just to starboard there was a low, cavelike opening in the hull, the edges mossy and jagged. I let myself sink down to peer inside with them. We hovered, and I added my large, bright light to Maddy’s smaller one, pointing into the interior. We weren’t going to penetrate. Neither Luca nor Maddy had the training, and I did not have the equipment. Our light captured the head of a green moray eel poking out of some rubble. A little sea turtle soared over the eel, hurrying out of the opening past us. She angled up, going for a breath. Luca turned to hurry after her. She sped up, frightened, giving him a disgruntled look over her shoulder. He stopped and simply hung vertically in the water, watching her flippers spinning her away.

I was touched by his instant and intuitive empathy. Whatever had happened between him and my stepdaughter, I couldn’t believe it was pure, manipulative evil. I hovered, my hands clasped, watching as Maddy took his arm and rolled him, showing him how to lie back and watch the turtle rise out of our range of visibility. Then she tugged him onward, down the side of the ship.

I stayed a few feet behind, letting them play their way down the slope, trusting Maddy. She stopped them right at fifty-five feet. They were still holding hands, though I wasn’t sure if this was underwater romance or security. He tried to move down, and she signaled no, showing him her depth gauge. He checked his, then gave an okay sign. He also checked his air again, forming a good habit, and reported it to Maddy without being asked. She reported her air level back. She’d used less, which was no surprise. New divers were air pigs, plus he was male and weighed more than she did.

Watching the kids spin and frolic like seal puppies, I felt my headache abating. The underwater magic was doing its good work in me. The ocean seemed large enough to hold the truth, and me, and even Roux, with room enough to be at peace. We didn’t see the other group at all, and Roux’s literal vanishing into the depths helped, too. When Luca’s air gauge read 1800 psi, I signaled to turn the dive, and we worked our leisurely way back to the anchor line.

Once we reached it, Luca did a perfect pre-ascent check, signaling, noting his time, and then looking up, his hands raised over his head to protect it. We flutter-kicked gently up, deflating as we went, though once I had to take Luca’s hose and vent air; he was rising too fast. At fifteen feet we made our safety stop, hovering and letting our bodies decompress while a trio of barracuda hung in the water watching us.

When we surfaced, Luca’s eyes were positively glowing. He swapped his regulator for his snorkel, pausing in between to say to Maddy, “Oh, my God!”

“I know, right?” she said, swapping out her own regulator.

She headed for the ladder first, handing her fins up to Winslow. He took them, looking past her to me. I felt a shiver in my spine when I saw his face, concerned and questioning. I gave him the okay sign, but he did not signal back.

I heard him call to Captain Jay, “Dad? Come here a sec?”

Luca headed up the ladder next. Winslow helped him aboard, but he was still darting glances at me, his broad, brown forehead wrinkled. As soon as Luca was out of the way, I passed my fins up to him.

“Where’s Roux?” he asked me, quiet, as I came up.

I dropped my regulator out of my mouth.

“She’s with the Babbages,” I told him, but as I climbed aboard, I saw that all three Babbages were already sitting in the shade of the canopy, eating oranges.

“They came up fifteen minutes ago,” Winslow said. I hadn’t seen them pass us. All my focus had been on the kids, plus they could have come up the other side. Winslow was still talking. “Mark got low on air, but she had more than half her tank. He said she joined your group?” Mark had a good seventy pounds on her; he would have used his air up much faster.

“We didn’t see her at all,” I told Winslow.

Captain Jay was scanning the water. I turned, still in my gear to help Jay look, and so did Winslow. My mind was racing. The sea was relatively calm. If there were bubbles, they would not be hard to find. But there was nothing.

“Hey, where’s Roux?” Mark called behind us.

“What?” Maddy said. She’d just finished helping Luca out of his BCD.

I ignored them, looking over the site, still bubble hunting. My heart was pounding. A thousand different things were happening in my head, too fast to catalog or even comprehend. I could see only one thing true and clear: No bubbles meant no breath. No breath meant—

“She was with you,” Luca said. His voice had gone high, edged in hysteria.

Mark was talking, fast and defensive. “No, she went to join your group. You guys were right there. We saw you.”

“You left her?” Luca said, the pitch of his voice going higher.

“You were twenty feet away,” Mark almost sounded pleading, but I kept my eyes on the water, seeking.

No bubbles. No breath.

No Roux. I felt sweat break out all over my body, inside my wet suit. I’d dreamed of this, a world with no Roux. In my dream it had made everything so easy, but now her son was standing right behind me.