Six Americans are tasked by a frontier medical examiner with retracing the footsteps of three dead migrants — three of the nearly 6,000 illegal immigrants who perished in the desert in the last 15 years while crossing from Mexico. Gathered at the morgue, the participants are handed three case files and told, “We’ve given them a name. You must give them a story.” The six, from all walks of life, first explore the issue on the U.S. side, embedding with law enforcement and Arizona ranchers angry at the cartels that now control not just the drug trade but the migrant routes as well. Then, split into three groups, they head for Mexico and Central America, learning about the lives of the migrants they’ve been asked to follow. In a twist, the medical examiner instructs the six to work their way back to the United States alongside real migrants by whatever means necessary … on river rafts, on foot through gang-controlled jungle and, once regrouped, on top the infamous cargo train known as La Bestia. Finally, from cartel-held Sinaloa state, they attempt the journeys that proved fatal to their assigned migrants — a dangerous trek through the Arizona desert. They’ll live. But will they learn?