Manuel Huerga chose Daniel Brühl, whose mother is Spanish, to play Salvador because he didn't want to tell a Spanish story, but a universal drama. This was the first time Brühl filmed in Barcelona, his place of birth.
At a certain point (rather early) in the movie, the song "Eimaste Dyo" ("We Are Two") by Mikis Theodorakis is heard, not with Greek lyrics though. The song was written during (and lyrically refers to) the common imprisonment (and the tortures accompanying it) of Mikis Theodorakis and Andreas Lentakis, during the dictatorship period in Greece (1967-1974).
Andrea Ros's debut.