All the prison scenes and the studio interiors were shot in chronological order as Fred Cavayé felt it would be important for the actors and the evolution of their characters.
The idea for the film came from Guillaume Lemans. Once Fred Cavayé got involved, the two men started out by working on the film separately before sharing their ideas. Cavayé then wrote the first draft of the screenplay himself, and so on.
Père Julien is shown discovering and reading what appears to be an airline ticket in Julien's assumed name ("DUVAL/OLIVIER") for travel from Liège, Belgium, to San Salvador, El Salvador. Later, the Auclerts are depicted boarding an aircraft at what appears to be Liège Airport. Liège Airport is a small, regional airport with primarily freight and charter operations. The regular commercial passenger destinations from Liège are within Europe and the Middle East. If the Auclerts flew from Liège, they would have had either to fly a special charter flight, or else to connect to a flight at another airport in order to reach San Salvador.