Jonás Cuarón's Desierto opens on a truck moving across the desert at dawn, somewhere south of the US-Mexico border. In the back are fourteen passengers, all bound for the US via the time-honored method of slipping through the fence and trekking across the hot, dusty wasteland. Among them is the appropriately named Moises (played by Mexican international actor Gael García Bernal), who has made the trip before.
The truck breaks down and the voyagers, already apprehensive, have to get out and walk across the badlands, shepherded by a guy named Lobo. We can see that one of the travelers, a chubby man, has trouble keeping up. Also, a young woman named Adela (Alondra Hidalgo) is struggling with her traveling companion, who insists on pawing her. Adela and Moises naturally gravitate to each other.
Meanwhile on the US side, a scruffy, wiry vigilante named Sam (Jeffrey Dean Morgan) drives up and down the line in his pickup, armed with a hunting rifle and an attack-trained German shepherd dog called Tracker, muttering racial slurs to himself and itching to make us all "safe" from undocumented folks like Moises and Adela. When Sam bumps into a government Border Patrol officer, they can only sneer at each other. Trigger-happy "patriot" Sam and the little band of newcomers are on a collision course, and it will get bloody.
That's about all there is to the plot, but director Cuarón, son of superstar filmmaker Alfonso Cuarón (Gravity), turns this slim tale of strife into one of the most nerve-jangling adventures of the season. In the spirit of such thrillers as Anthony Mann's Border Incident and Cornel Wilde's The Naked Prey, the screenplay — written by Jonás Cuarón and Mateo García, with various Cuaróns as producers — pits the hunted against the hunter in a stark contest of survival in an unforgiving landscape.
In the film's briskly paced 88 minutes, there's no time for showpiece speeches or in-depth characterization. TV veteran Morgan (Grey's Anatomy) portrays the hate-filled Sam with a laconic physicality — Sam's lengthiest lines of dialogue are addressed to his dog. As the frightened Adela, actress Hidalgo's chief task is to cower behind vegetation. Even movie star García gets put on the hurry-up griddle. As an actor who impersonated the young Che Guevara for Walter Salles (The Motorcycle Diaries), an obsessed Pedro Almodóvar-style pretty boy in La Mala Educación, and a desperate lower-class dog fighter in Alejandro Iñárritu's Amores Perros, the 37-year-old García carries a surprisingly wide range of types in his bag of tricks. Some of his very best parts have been supplied by the Cuarón family — a would-be playboy in Alfonso Cuarón's Y Tu Mamá También, and a clownish provincial futbolero (once again alongside frequent costar Diego Luna) in Rudo y Cursi by Carlos Cuarón, brother of Jonás. In Desierto, things develop so quickly that Moises spends all his screen time simply trying to survive. He interacts with his daughter's keepsake teddy bear — the one with the telltale ring tone — as much as he does with any of his fellow undocumented immigrants.
Stripped-down and brutal, Desierto nevertheless assumes mythic proportions when set against real-life contemporary anti-immigrant bombast and its accompanying threat of home-brewed violence. Moises, Adela, and their companions only want to move to a place where they can earn a better living — for Moises, that happens to be Oakland, where his young daughter resides. They arrive in the new land unarmed and full of hope. Sam, on the other hand, shows us by his actions that he's willing to murder men, women, and children in order to prevent them from trespassing on his homeland. Precisely what motivates him and why, we never find out, but it becomes a clear case of kill or be killed. Filmmaker Cuarón's sympathies are implicit but never obtrusive. The only neutral observers are the rattlesnakes. Desierto is a cruel postcard from the America we'd probably rather not think about.