A baby born in the Auschwitz-Birkenau barracks in October 1944. A Sonata composed by a young German officer, on the same date, also in Auschwitz. Two stories that cross paths and complete each other. Decades later, Amalia, Portuguese daughter of a German father, starts to lift the veil that covers the Nazi past of the family from a musical score revealed by an unknown great-grandmother, signed by her grandfather Friedrich and entitled Für Haya (for Haya).

The question of whether her grandfather, considered deceased before the end of the Second World War, could be alive in Rio de Janeiro, leads her to cross the ocean and meet a Holocaust-surviving Jewish couple, Adele, and Enoch. The rise of Nazism in Berlin, the saga of the Hungarian Jews of Transylvania, the mysteries that occurred in the extermination camp in Poland and the post-war era in a house full of secrets in a Potsdam lake offer the paths that Amalia will travel to piece the puzzle together.