Meet Renee and Herta, two sisters who faced the unimaginable -- together. This is their true story. As Jews living in 1940s Czechoslovakia, Renee, Herta, and their parents were in immediate danger when the Holocaust came to their door. As the only hearing person in her family, Renee had to alert her parents and sister whenever the sound of Nazi boots approached their home so they could hide. But soon their parents were tragically taken away, and the two sisters went on the run, desperate to find a safe place to hide. Eventually they, too, would be captured and taken to the concentration camp Bergen-Belsen. Communicating in sign language and relying on each other for strength in the midst of illness, death, and starvation, Renee and Herta would have to fight to survive the darkest of times.