The boat captain looked at me like I'd asked him to sail to the moon. "You want to go where?" Niko squinted against the morning sun, his weathered hands still gripping the wheel of his modest fishing boat. I pointed again at the coordinate I'd scribbled on a napkin—a seemingly random spot in the middle of Bacalar Lagoon that my Airbnb host's grandmother had whispered to me the night before.

"La abuela says there's something special there," I explained in broken Spanish, feeling slightly ridiculous. "A sandbar that... appears?"

Niko's expression shifted from skepticism to intrigue. After thirty years of ferrying tourists around Mexico's "Lagoon of Seven Colors," he'd thought he'd seen everything. But Doña Carmen's grandmother had lived on these waters for eight decades. If she said there was magic to be found, maybe it was worth investigating.