One by one the sound flotillas drifted east. On each rig were not only musicians but handlers, hookers, lookers, lookers-on. There were whole city blocks of people dancing on the rolling trucks: bodybuilders with built bodies and no clothes but those Speedos; women with spinnaker chests; headdresses; spears—it made Mardi Gras look like a convention of accountants. I heard the reincarnation of John Bonham, who turned out to be an unassuming white guy in shorts, a T-shirt, and a baseball cap. His lower body churned out a stately backbeat, while his twelve-armed upper body whirled 359 degrees, letting fly. Somehow what he generated reached inside your rib cage. It was a mind infarction, like applying chest paddles to the groin.

This heartbeat throbbing was the world; it was real culture, a sound that amplifies, fuses people with one another, reassures. As this drummer set the songs going, women leapt to their feet and gyrated in the balmy night. They would dance with anyone, even a cadaverous loser like me. They grabbed me. They implored. When I replied in flawless Portuguese that I was there for ethnographic purposes only, they got over it fast. They handed me their babies, and everyone smiled. Babies slept in my lap while their mothers shook. It was actually quite peaceful, in a delirious way. Men were willing to dance, but the women had to dance.

When I fell asleep toward morning, I felt I had undergone initiation to life itself. Something had been cured.

Maps of Brazil reveal three north-eastern states that march horizontally across the country's shoulder: Ceará, Piauí, and Maranhão, all of which edge into the warm Atlantic just below the equator. The terrain is grandiose, magnificent, and complex. To travel in this New World is to see the America Amerigo saw. It looks and feels just as it would have five hundred years ago: wild, vigorous, open, and raw. There are lush tropical deltas, river crossings, and, most of all, beaches—mile upon mile of ocean and sand, miraculously uninfested by the commercial appetites of modern man. There are also poor farms, desert, the dry hinterlands that Brazilians call the Sertão. It is a thorny scrubland, its red soil baked as hard as a clay flowerpot. The parched heat seems to contribute to an almost permanent state of social distress. Periodic droughts have set off human stampedes of migration to the cities farther south; as much as eighty percent of the population has left in the past forty years.

Before we set out from Fortaleza, Senhor Ramos, our guide, spread the maps on the hood of the Land Rover that would be our headquarters for the next two weeks. We were an affable, multilingual lot: a photographer from New Zealand, a photo assistant from Argentina, and me. With very little idea of what to expect, our team set out to cross six hundred miles of open coast. All along the way, we would be hugging the shore, which meant we had to travel by four-wheel drive and boat. We would make our way from Fortaleza to Jericoacoara, a beachside outpost of relative modernity that is but a tiny point in 250 miles of open sand, and then from there to the delta of the Parnaíba River, the third-largest delta in the world, to Lençóis Maranhenses, a national dune park of unearthly grandeur, and end up in the colonial city of São Luís, the capital of Maranhão. Looking at the maps, things didn't seem that far apart. But traveling overland had a way of taking longer than expected.