In the Nazi concentration camp Terezin, imprisoned conductor Rafael Schächter led his fellow inmates to fight back with art and music, including a performance of one of the world's most difficult and powerful choral works, Verdi's Requiem, re-imagined as a condemnation of the Nazis. The film also tells the story of conductor Murry Sidlin, who decades later brought the Requiem back to Terezin in t…