Cold daylight breaks over one desert, two nations and three men, nervously walking north.
They are underdressed for the freezing temperature, their shoulders hunched beneath frayed backpacks and their eyes scan the horizon for movement. At the same moment, the Americans who will spend the day trying to catch them are assembled for their morning muster.
"We're going to continue to send bodies to Tucson detention for Operation Streamline," an officer announces to the 50 men in the room. Border Patrol refers to illegal crossers as "bodies," and on average the Nogales station catches more than 1,000 a day. They also seized more than 450 tons of marijuana last year, making this the busiest 32-mile stretch for the Border Patrol on the entire southern border.
At 9:30 a.m., Kevin Carlos crouches beside a trail of faint footprints that zigzag across the sand. He is one of the Shadow Wolves, a small unit of American Indian Immigration and Customs Enforcement officers who use age-old techniques to track border jumpers and drug runners crossing the Tohono O'odham Nation.
From the tracks he can tell there are eight footsore men carrying bales of marijuana toward the nearby mountains.
"In the last two miles they've rested eight times," he says. "Nobody rests that much unless they're tired. And when they stop they're setting down packs." These mules didn't bother with the common practice of tying scraps of carpet to their feet to confuse the trackers and the footprints eventually lead to 350 pounds of marijuana. The smugglers will be gone.
This reservation is the size of Connecticut, straddling both sides of the border. The Tohono O'odham lived here centuries before Mexico and the United States existed, but if the Shadow Wolves see the irony, they won't admit it.
"We think about it," says Ortega. "But we've got a job to do."
It is just after noon on the Mexican side and a car full of people creeps toward the border. "They are going to go chest to the ground," says the driver, "so they aren't caught by the cameras and sensors." The driver is a coyote, a professional people smuggler who works out of the village of Alter, about 60 miles south. He charges $2,000; $500 up front and $1,500 if his customers make it across.
The group climbs out of the car and jogs toward a nearby ravine. "Hide, hide right now," the coyote yells from the driver's window. "The other guide is coming and is going to take you under. I'm going back for another trip."
Moving people and drugs north is now a billion-dollar-a-year business in this corner of the desert and the multibillion-dollar effort to stop it is becoming more evident in Arizona, including communities well north of the border.
Roger Beal owns the grocery in the tiny town of Arivaca, 12 miles north of Mexico. He points out the bus parked at the end of town ready to take detainees away, the helicopter buzzing overhead and the new high-tech surveillance tower that dominates the skyline.
"We're for the Border Patrol doing their job," he says. "But the way it's being done it feels like we're south of the border here."