The film by Venezuelan director Lorenzo Vigas centres around young Hatzin, who has gone to collect the remains of his father, one of countless people who suddenly vanished in northern Mexico only to be found in a mass grave.

On his way home, Hatzin meets Mario, a man who looks like his father, who reluctantly takes the boy under his wing. Hatzin then learns Mario makes a living hiring desperate people to work in the garment factories dotting the barren landscape.

“The Box” is the closing part of Venezuelan director Lorenzo Vigas’s trilogy about fraught relationships between fathers and sons. His previous film, “From Afar”, took the top prize in Venice in 2015.

He said working in factories like the ones shown in the movie, with row after row of labourers toiling on sewing machines and steam presses to make jeans, is the only way to make ends meet for many Mexicans.

“Everyone in the north of Mexico depends on the factories,” Vigas said. “I am not saying that all the factories treat people badly, but you have factories that imprison their workers, much worse than what you see in ‘La Caja’ (The Box).”

Vigas shot the film in the northern Mexico state of Chihuahua, where drug gangs are rife and can be easily blamed for the sudden disappearance of those who work in the factories.

Senseless violence in everyday life is also a theme in “Sundown”, another Mexican film screening at Venice by director Michel Franco.

Starring Tim Roth and Charlotte Gainsbourg, the film follows members of a wealthy British family vacationing in the resort city of Acapulco, where hitmen come by boat to kill their targets and armed soldiers are seen patrolling the beaches.

“As a Mexican, you get used to hearing about violence every day,” Franco said.

“I am very much against the idea of saying it’s normal, it’s part of our lives. Cinema is a good way to trigger a conversation about how it shouldn’t be.”