Andy was well aware the Mamoré river, which ran south to north, acted as a border between the two countries; the Bolivian city of Guayaramerín on the western side and the Brazilian city of Guajará-Mirim to the east.

“Looks about the same over there,” Andy replied.

And it did, especially from the air. A small municipality—both cities had populations of around forty thousand—surrounded by a never-ending sea of green.

The National Geographic writer nodded in agreement. “That it does.”

Nathan Buxton and Andy were two of the five remaining members of the expedition team. After waking early, the entire team, all nine of them, had boarded a plane—thankfully, one much larger than the charter jet—and flown the two hours from La Paz to the Guayaramerín airport. From there they took vans to a small airstrip where a blue AStar helicopter, Holland’s partner, and an enormous amount of supplies awaited them.

Holland’s partner, Ian Rixby, had taken an advance flight to the landing zone to make sure there was a large enough clearing for the helicopter to land. The prospective LZ was on the bank of a small river that broke up the endless sea of green canopy. Unfortunately, there wasn’t quite enough room on the riverbank, and the ex–military man was forced to repel from the helicopter, and after five hours with a chainsaw and a machete, he was able to clear a thirty-foot landing radius where the riverbank met the brush.

The AStar helicopter, with its chipped blue paint, had a maximum capacity of six, so the expedition team would have to fly the forty minutes to the landing zone in two convoys. The first convoy was Roth, Holland, Rixby, and both cameramen, plus the head of Bolivian archaeology, Alejándro Cala.

Dr. Farah Karim was insistent she be on the first flight to make sure the landing zone didn’t have any possible archaeological significance, but it was decided the heavyset Cala made more sense.

The slight Farah would join Andy, Libby, Buxton, and Bolivian anthropologist Bernita Capobianco on the second flight. Smaller in both number and stature, they would be able to take supplies with them. Which was vital, considering that a storm was brewing on the eastern horizon. It was doubtful the AStar would be able to make more than two flights, and it was likely that the majority of the supplies—portable generators, stacks of bottled water, toilet paper, tarps, folding tables, tents, chairs, cots, and other necessities—wouldn’t arrive until the following day.

“Do you think they speak Spanish or Portuguese in—” Buxton glanced down at the unfolded map in his hand. “—Guajará-Mirim?”

“Portuñol,” Andy replied.

Buxton cocked his head slightly.