She threw her arms around my neck. “I missed you,” she said. “Sorry about before.”

“I am, too,” I said, patting her back awkwardly. “So, let’s talk.”

She pulled away. “Not here. There’s a better place. A special place.”

“I don’t know …”

She took my hand. “Don’t be that way. You’ll adore it, I promise. And when we get there, I’ll tell you everything.”

I was pretty certain it was a plot to get me to make out with her, and had I been any older or wiser, or one of those guys for whom make-out sessions with hot girls were so frequent as to be of no consequence, I might’ve had the emotional and hormonal fortitude to demand that we have our talk right then and there. But I was none of those things. Besides, there was the way she beamed at me, smiling with her whole self, and how a coy gesture like tucking her hair back could make me want to follow her, help her, do anything she asked. I was hopelessly outmatched.

I’ll go, but I’m not going to kiss her, I told myself. I repeated it like a mantra as she led me across the bog. Do not kiss! Do not kiss! We headed for town but veered off toward the rocky beach that looked out onto the lighthouse, picking our way down the steep path to the sand.

Reaching the water’s edge, she told me to wait and ran off to retrieve something. I stood watching the lighthouse beam wheel around and wash over everything—a million seabirds sleeping in the pitted cliffs; giant rocks exposed by the low tide; a rotted skiff drowning in the sand. When Emma came back I saw that she had changed into her swimsuit and was holding a pair of snorkel masks.

“Oh no,” I said. “No way.”

“You might want to strip to your skivvies,” she said, looking doubtfully at my jeans and coat. “Your outfit’s all wrong for swimming.”

“That’s because I’m not going swimming! I agreed to sneak out and meet you in the middle of the night, fine, but just to talk, not to—”

“We will talk,” she insisted.

“Underwater. In my boxers.”

She kicked sand at me and started to walk away but then turned and came back. “I’m not going to attack you, if that’s what you’re in a knit about. Don’t flatter yourself.”

“I’m not.”

“Then quit mucking about and take off those silly trousers!” And then she did attack me, wrestling me to the ground and struggling to remove my belt with one hand while rubbing sand in my face with the other.

“Blaggh!” I cried, spitting out sand, “dirty fighter, dirty fighter!” I had no choice but to return the favor with a fistful of my own, and pretty soon things devolved into a no-holds-barred sand fight. When it was over we were both laughing and trying in vain to brush it all out of our hair.

“Well, now you need a bath, so you might as well get in the damned water.”

“Okay, fine.”

The water was shockingly cold at first—not a great situation vis-à-vis wearing only boxer shorts—but I got used to the temperature pretty quickly. We waded out past the rocks where, lashed to a depth marker, was a canoe. We clambered into it and Emma handed me an oar and we both started paddling, headed toward the lighthouse. The night was warm and the sea calm, and for a few minutes I lost myself in the pleasant rhythm of oars slapping water. About a hundred yards from the lighthouse, Emma stopped paddling and stepped overboard. To my amazement, she didn’t slip under the waves but stood up, submerged only to her knees.

“Are you on a sandbar or something?” I asked.

“Nope.” She reached into the canoe, pulled out a little anchor, and dropped it. It fell about three feet before stopping with a metallic clang. A moment later the lighthouse beam swept past and I saw the hull of a ship stretching beneath us on all sides.

“A shipwreck!”

“Come on,” she said, “we’re nearly there. And bring your mask.” She started walking across the wrecked boat’s hull.

I stepped out gingerly and followed. To anyone watching from shore, it would’ve looked like we were walking on water.

“How big is this thing, anyway?” I said.

“Massive. It’s an allied warship. Hit a friendly mine and sank right here.”

She stopped. “Look away from the lighthouse for a minute,” she said. “Let your eyes get used to the dark.”

So we stood facing the shore and waited as small waves slapped at our thighs. “All right, now follow me and take a giant breath.” She walked over to a dark hole in the ship’s hull—a door, from the look of it—then sat down on the edge and plunged in.

This is insane, I thought. And then I strapped on the mask she’d given me and plunged in after her.

I peered into the enveloping blackness between my feet to see Emma pulling herself even farther down by the rungs of a ladder. I grabbed the top of it and followed, descending hand over hand until it stopped at a metal floor, where she was waiting. We seemed to be in some sort of cargo hold, though it was too dark to tell much more than that.

I tapped her elbow and pointed to my mouth. I need to breathe. She patted my arm condescendingly and reached for a length of plastic tubing that hung nearby; it was connected to a pipe that ran up the ladder to the surface. She put the tube in her mouth and blew, her cheeks puffing out with the effort, then took a breath from it and passed it to me. I sucked in a welcome lungful of air. We were twenty feet underwater, inside an old shipwreck, and we were breathing.

Emma pointed at a doorway in front of us, little more than a black hole in the murk. I shook my head. Don’t want to. But she took my hand as though I were a frightened toddler and led me toward it, bringing the tube along.

We drifted through the doorway into total darkness. For a while we just hung there, passing the breathing tube between us. There was no sound but our breaths bubbling up and obscure thuds from deep inside the ship, pieces of the broken hull knocking in the current. If I had shut my eyes it wouldn’t have been any darker. We were like astronauts floating in a starless universe.

But then a baffling and magnificent thing happened—one by one, the stars came out, here and there a green flash in the dark. I thought I was hallucinating. But then more lit up, and still more, until a whole constellation surged around us like a million green twinkling stars, lighting our bodies, reflecting in our masks. Emma held out a hand and flicked her wrist, but rather than producing a ball of fire her hand glowed a scintillating blue. The green stars coalesced around it, flashing and whirling, echoing her movements like a school of fish, which, I realized, is just what they were.