As a reporter, Jacques Peretti has spent his life investigating important stories. But there was one story, heard in scattered fragments throughout his childhood, that he never thought to investigate. The story of how his mother survived Auschwitz.

In the few last months of the Second World War, thirteen-year-old Alina Peretti, along with her mother and sister, was one of thirteen thousand non-Jewish Poles sent to Auschwitz. Her experiences there cast a shadow over the rest of her life.

Now ninety, Alina has been diagnosed with dementia. Together, mother and son begin a race against time to record her memories and preserve her family's story. Along the way, Jacques learns long-hidden secrets about his mother's family. He gains an understanding of his mother through retracing her past, learning more about the woman who would never let him call her 'Mum'.