AT SIX O'CLOCK THE NEXT MORNING, I wasn't so sure. We were leaving Virgin Gorda for the four-mile swim to Ginger from the Baths, a boulder-strewn volcanic peninsula that looks more like Joshua Tree than the Caribbean. This was where, according to the Australian woman, we'd have our asses handed to us: The ocean has had thousands of miles to build up its tempo here before it pounds the rocky beach. Indeed, beyond the rocks, I was sure a hurricane waited for us. I felt like I could see shark fins, roiling whitecaps, and marauding speedboats everywhere.

"Hey, Hod," Hopper called, casually treading water beside me. "What a perfect day to begin our journey, huh? Let's get going, though. Get this under our belt."

"Yeah, you guys go," Paolo said from the safety of his speedboat, which wasn't turning out to be so speedy. Not only was it impossible to start, it also wouldn't plane. We'd be half eaten by the time they ever got to us.

Thankfully, Saint Jude, patron saint of lost causes, was smiling down on us: The winds were out of the east-northeast instead of the prevailing southeast, and both the water and the sky were clear and warm. And a chain of rocky islands guards much of the crossing from the Baths to Ginger, blocking the east wind and creating shallow water most of the way.

We didn't see much. Millions of tiny glistening fish streaked along the surface, so small they seemed more optical illusions than aquatic life, and a couple of barracuda swam urgently toward us and then appeared to back up when they saw our size, as if thinking, Oops—my bad. That was it, if you discount the hundreds of jellyfish attacking us. For an animal that has no brain, bones, eyes, or heart, the thimble jelly is a tricky little predator, filled with stinging cells called nemocysts that inject their venom into you with teeny-tiny harpoons.

As the minutes, a half hour, and then an hour ticked off and the water got deeper and deeper, I grew ever more freaked out, despite our mother hens, Paolo and Derik, constantly hovering within a few hundred yards. For some reason, I was most afraid of sharks in the deeper water, although most attacks happen in shallow areas and, even more pertinent, my own not-so-casual research showed that there have been only four unprovoked shark attacks in the Virgin Islands in the past 100 years. Even so, I took comfort in the fact that Hopper was in the rear, pulling the surfboard.

Suddenly, Hopper stopped swimming. We were about a quarter-mile off Ginger Island in 100 feet of water. Not a good place for a chat.

"We gotta do something different," he said, taking a swig from the water bottle strapped to the board.

"Why would we do that? Let's keep going," I answered, a little pissy. "We're nearly there."

"We're not going anywhere. I've been watching that white scar on the cliffs over there for ten minutes. We haven't moved."

Now that we were no longer in the lee of the outlying islands, those whitecaps I'd imagined had become very real, along with an accompanying 15-knot wind. The one-knot current our chart indicated was more like two to three. Our destination on Ginger—a lagoon behind a northeast peninsula—was now upwind.

We strapped on our Zura Alphas, flexible, lightweight fins that would give us just enough of an advantage to compensate for the wind and current. Except they didn't. We swam for another ten minutes, but we were still going backwards.

Clearly outpowered, we decided to put the wind on our port beam and head for the less desirable north shore, where there appeared to be a boat anchored. Fifteen minutes later, we tumbled ashore, arriving like bewildered shipwreck survivors as breakers sent us rolling over spiny sea urchins. What had looked like an inviting beach 400 yards away turned out to be a 15-foot-wide shelf of broken coral. And the boat that was going to be our salvation was actually a wrecked charter sailboat, itself forlornly waiting to be rescued.

That's how we spent our afternoon—forlornly waiting. While Paolo and Derik went back to Virgin Gorda to get their boat fixed, Hopper and I swam another mile to the western edge of the island and generally wilted in the inescapable sun. That evening, they finally returned with food, drinks, and a still-broken boat.

"Well, day two down and no shark. That's a good thing," I said, toasting with a shot of rum-spiked Gatorade.

Derik looked at Paolo, as if to ask, Should we tell him? "Paolo did see this really big thing come up behind you once."

"Really big," Paolo said, smiling.

That night, camping through two storms on the beach without a sleeping bag, rainjacket, or even a tarp, I dreamed of shark-shaped jellyfish eating holes through my sodden brain. About the only thing that made me happy was watching Hopper hiding from the rain, huddled under a fish crate.