From seaward, the human eye can distinguish prominent shapes—the lighthouse or Freedom Tower or Turkey Point—at eight miles. To a person of my height standing above the waterline, the horizon is two and a half miles away: a stone’s throw. Considering the blue expanse of ocean in my vision and the thousands of glassy wavelets and the fathoms of veiled blond seafloor, I would have thought I could see to Cuba. I felt tremendously calm. I felt caught in a swell of well-being. Maybe I was lulled by the waves and the sunlight, or maybe I believed that there were no stakes on vacation, and had abandoned my usual anxieties regarding the future, that unnavigable ocean. When I returned home, I knew, I would spend evenings on the front porch of my apartment house in Atlanta, where I’d lived and worked since graduating from college, chatting with my neighbors and slapping at mosquitoes. Soon the sunlight would weaken and blanch, and I would add a quilt to my bedspread and unpack the space heater. A smattering of my still-single college friends would get engaged or married, and I would swim through fits of loneliness like cold undercurrents. But that afternoon, on that clandestine ledge, I felt like a stowaway whose trip had begun. All I had to do was wait.

Splashing sounds came from beneath the house. “Where did it go?” said Kyle.

“I’ve got it,” Dennis said.

With some effort, I swung my legs to one side and eased my stomach onto the bare, warm wood. I peered over the ledge until I could see beneath the house. Dennis was lowering a squirming lobster into a crate filled with other lobsters; their antennae lashed through the slats. Fish darted around the boys’ legs. “Join your family,” said Dennis to the lobster, and I pushed myself back into a sitting position.

The boys splashed through deeper water and hauled themselves onto the dock. “They’re angry,” said Dennis, and Kyle said, “Sweetens the meat.” Their steps on the stairs were noisy and quick. I knew I should join them, but I felt fastened to that ledge, partly from inertia and partly from reluctance to try to stand in so tight a space. Below me, seven feet down, the sandy seafloor was covered by only a few feet of water: it would hurt if I fell, might even break a bone. Dennis called my name. I thought it would confuse him if I answered—where would it seem like my voice was coming from?—so I stood, carefully. Then I heard his steps on the stairs. “Frances!” His voice was gruff and resolute. It grew quieter as he moved down the dock, away from the house, then louder as he returned. “Frances!”

I closed my eyes. It was his concern, the throaty pitch of it, that moved me to answer, even before I could manage to get myself off the ledge. “Here,” I said. Then louder, “I’m here.”

He appeared beside the water tower, leaning out beyond the back of the house. His mouth was tight. “What are you doing?”

“Nothing,” I said. “Looking around.”

He glanced south, toward Soldier’s Key, then down at the water. “We wouldn’t want to lose track of you out here.”

“I wouldn’t want that either.”

The irritation slipped from his face. He looked around again, then stepped onto the ledge beside me. I edged over to give him room, and we stood with our backs to the wall, our arms at our sides. “Are you contemplating fate and the universe?” he said, not unkindly.

I smiled. I didn’t want to seem overly serious. “I like it here.”

“You’re welcome anytime.”

I wanted to say something about having felt like a different person all day, but I didn’t know what I meant or how he would respond, so I stayed quiet. He said, “My father was boating back from Bimini once, and he ran out of gas right out there.” He pointed. “He radioed the Coast Guard and told them he was ten miles northwest of the lighthouse, then his radio gave out. They didn’t find him for hours. By the time they did, it was night. He asked what had taken them so long and they said they’d been searching for him on the north side of Miami Beach. Then they’d realized he’d given his position wrong—the lighthouse was ten miles northwest of him, not the other way around. I look out there and I think, how could he make that mistake?”

I followed his stare into the thick blue distance, bare of markers or guides. It would take an enormous act of faith, I thought, to trust the jittery needle of a compass. “I can see how a person might get confused,” I said.

I don’t think Dennis meant to kiss me. He was leaning in to hear me, and when I turned our noses and cheeks met and—this amazes me still—neither of us backed away. Our mouths were uncertain. We kissed without embracing. We kept our eyes open. We could feel even then that we were at the beginning of something, I think—something that might go on and on before it ended. After, we faced each other.

“We could go skiing, if you want, before dinner,” he said. He reached toward my face. His fingers found my earlobe.

“I haven’t skied since college, and then it was in a lake.”

“It’ll come back to you.”

I could feel the warmth from his body and I could smell his clean, sun-soaked smell.

“If we’re going to go we should go,” he said, “or we’ll miss the daylight.”

I nodded. He stepped from the ledge onto the bottom floor of the house, then reached for my hand and pulled me over the gap. I walked ahead of him up the stairs, and as we went he kept one hand on the small of my back, the gentlest suggestion of a rudder.

The sun was easing toward the horizon by the time we headed off. We took Dennis’s father’s boat because it was more powerful and because, Dennis said, the hull of Marse’s boat was painted blue, which was bad luck. This was mariner lore: the sea might confuse the boat with itself and drag it down. I stood by while Marse affixed a towline and Dennis started the engine and Kyle handled the lines. The channel was dark and choppy and wide. Marse handed me a lumpy orange life vest and I tightened it at the chest and waist, but Dennis loosened it again. His knuckles brushed my stomach through the swimsuit. “It won’t come off,” he said, “but you don’t want it too tight.”

Our kiss rose in my gut. “I’m ready,” I said, and because the lie was so obvious, we both laughed. He went to the console and put the boat in gear. I stumbled when the boat moved. When I regained my balance, I noticed Marse watching me.

We agreed that Kyle would ski first, then I would ski, then Marse. Kyle rose on skis as if from land, as if the baton were a sturdy hand. I recollected all I knew about waterskiing: Treat the water like a chair. Bend your knees. Let the towline pull you up. Lean back. Relax. Kyle skipped over the waves, and the boat rounded the mouth of the channel and returned, passing the stilt house, before he fell. I don’t think he fell, actually—he threw his skis to the side and skidded, sending up white spray, then let go of the line. When we reached him, Marse asked if he wanted to go again, but he said he was wiped out. He climbed into the boat and took a beer from the cooler.

Dennis gathered the skis from the water—they were wooden, with a yellow stripe painted down the center of each. “Kyle will be your lookout,” he said to me. “He won’t take his eyes off you.”

“I’m an ace lookout,” said Kyle. He’d wrapped himself in a towel.

“Just don’t leave me there,” I said to Dennis. “When I fall, come right back.”

“I will,” Dennis said.

I slid into the water, avoiding the stilled propellers. I struggled with each ski, then stretched my legs in front of me, drifting from the boat. The water cupped and jostled me; I tipped and righted. Dennis gave me a thumbs-up and I returned it awkwardly, and then the line spun out and I started to rise. Halfway up, I shifted and wobbled, and then I was hunched with my elbows over my knees. I straightened as much as I could without losing my balance. Kyle stood at the stern, watching me. Beneath my skis, the water whitened with friction and speed. The boat’s wake, like the crease of an open book, stretched between the engine and my skis. We sped by one stilt house, then another. Kyle clapped for me and pumped a fist in the air. I tried to turn my grimace into a smile. Marse moved to stand beside Dennis, leaning toward him to be heard over the engine.

The sky was working up to dusk, the light so clear that I could make out the shoreline along Key Biscayne. Dennis’s back was a landscape of swells and shadows. Marse had a hand on his arm. She was talking and he was nodding. I took one hand from the baton and sliced it through the air in front of my neck: I quit. Kyle turned to tell Dennis, and I let go. I skidded and started to sink. Dennis waited a few seconds before turning—maybe the channel was too narrow, or there was another boat—and as I waited, I closed my eyes and tasted the salt on my lips. There were dune-shaped ripples on every wave: ripples on waves on tidal swells. I felt like a very small piece of a very large puzzle.

The sound of the engine grew louder, then shifted as Dennis put the boat into neutral. I opened my eyes. Dennis leaned over the gunwale. He pulled my skis out of the water and reached for me. Marse was suited up by the time I was back in the boat. She dove in, and Dennis fed a ski into the water. I went to hand her the other one, but he stopped me. “She’s going to slalom,” he said.

“Wow,” I said.

“You were good.”

“I almost fell getting up.”

“But you didn’t.”

“Let’s go,” said Marse. “Start out faster this time.”

“You’re her lookout,” said Dennis to me.

She skied beautifully. The way her body responded to each wave, her rubbery maneuvers, reminded me of a child on a trampoline. Her body held no resistance, no fear. We neared a stilt house and I alerted Dennis, but he just nodded and stayed the course. He was so intent that his jaw clenched and his eyes narrowed. I watched him for a moment, and when I looked back at Marse, she wasn’t there. “Stop!” I said.

Dennis slowed the boat before looking around, which gave me a moment to search the water for Marse’s orange life vest. I found her a ways back, in the dead center of the channel. Sit up, I thought. Show yourself. Dennis started his turn. “I’m sorry,” I said. “I looked away.”

“You can’t look away,” he said.

I pointed at Marse until he spotted her. Beyond her, a speedboat with a high red hull cruised toward us. “Hurry up,” I said.

“I can’t,” said Dennis. “We’ll fly right by her.”

When we were close, Marse waved, rising from the water, and as she did, the red boat adjusted its course by a degree or two, and there were twenty yards of water between Marse and the red boat when it passed her. Dennis and the captain exchanged gestures of greeting. We were supposed to be flying a flag—I know this now—to convey to other boaters that we had a skier in the water. It was the kind of rule that most boaters ignored, which made me frantic: it’s a terrific idea, that flag.

“Were you planning to leave me here?” said Marse. She spat water.

Dennis cut the engine. The boat’s shadow swallowed Marse, and I noticed how dark it had become. Orange sunset soaked into the horizon. “Sorry about that,” said Dennis.

Marse held up her ski and I pulled it into the boat. Dennis reached to give her a hand, but she was unfastening her life vest. “You go on,” she said. “I’m going to swim.”

The stilt house was about three hundred yards away. I had no idea how far a person could swim. “No way,” said Dennis.

Marse handed the life vest up to me and, not thinking, I took it, but Dennis snatched it from me and threw it down to her. “It’s getting dark,” he said. “Get in the boat.”

“Don’t be such a bore,” said Marse. She kicked away from us, leaving the life vest behind. Kyle pulled it out of the water. Dennis started the engine and maneuvered until we were puttering along beside her. Her stroke was fast and smooth. She raised her face from the water. “Go away,” she shouted.

Kyle stood beside me at the gunwale. “Marse,” he called, “I’m hungry. Get in the boat.”

To Kyle, I said, “This is my fault.”

“Not really,” he said, but I saw in his expression that he didn’t wholly trust me. Marse’s stroke had started to falter. The tide was probably coming in, canceling her efforts. She could have swum all night just to keep the stilt house in sight.

“Dennis,” I said. I thought he should have been doing something.

“She’ll get tired,” he said.

“She won’t,” said Kyle. When Marse tilted her head to breathe between strokes, her face was very red. Quietly, Kyle said to me, “Tell her you’re sorry.”