Oscar (Saenz de Heredia) lives in Almeria, Spain, where he works as a guard at a salt mine. He is thirty years old, lives alone and his existence could not be more gray and monotonous. Each day, when his turn ends, he returns home and the first thing he does is look at the mailbox, but the letter he is waiting for never arrives. But one day, Oscar gets word that grandfather has been transferred to a hospital. His sister Maria (Veronica Echegui), who now lives in Paris, comes to Almeria to visit her grandfather. Maria is accompanied by her boyfriend Jean (Denis Eyriey), who tries to keep a distance between the two siblings. It becomes clear that Oscar and Maria share an ugly secret that she wants to keep hidden at all costs, leading to an grim tension that grows between her and her brother.