Sixteen-year-old Catholic Stefania Podgórska has worked in the Diamant family's grocery store for four years, even falling in love with one of their sons, Izio; but when the Nazis came to Przemyśl, Poland, the Jewish Diamants are forced into the ghetto (and worse) but Izio's brother Max manages to escape, and Stefania embarks on a dangerous course--protecting thirteen Jews in her attic, caring for her younger sister, Helena, and keeping everything secret from the two Nazi officers who are living in her house.