Priest Julian's dedication to the Villa residents bears a striking resemblance to real life Priest of the Villa, Carlos Mugica. Although born into a well off middle class family, Mugica emphasized with the poor in Argentina particularly in Buenos Aires. He preached liberation theology to Villa residents and is hailed as a Third World priest similar to Oscar Romero from El Salvador. Mugica also supported both spiritually and unapologetically the liberation struggles of the poor and revolution students. His political alignment to left wing radical politics (revolutionary) in the 1960s and continued work among the villa's habitants, accumulated in his assassination in 1975.
The film is mostly set in the villa, one of many slums across Buenos Aires. The rest of the city is only seen in reflection representing the physical and figurative isolation of the villa from the larger city.
Belgian actor Jérémie Renier didn't speak Spanish before this film. He learned his lines by heart and after three months he could understand everything because Spanish is close to French, his native language.
The Dardenne brothers (Jean-Pierre Dardenne and Luc Dardenne) suggested Jérémie Renier to director Pablo Trapero.