At 22, filmmaker Serena Dykman had always known that her maternal grandmother, Maryla Michalowski-Dyamant, was an Auschwitz survivor, but she never dared or cared to inquire more about the Nana she had lost at 11. But after witnessing the terrorist attacks in Paris and Brussels, Serena decides to read her grandmother’s memoir and makes a startling discovery: More than simply a survivor, Maryla is revealed as a woman who devoted her life to fighting intolerance. Inspired, Serena embarks on a journey with her mother, Alice, and a film crew to retrace Maryla’s life, from her native town of Bedzin, Poland; to the horrors of Auschwitz, where she served as Dr. Mengele’s translator; to Brussels, where she emigrated after the war. Mother and daughter assume Maryla’s voice, reading excerpts of the memoir in front of key places from Nana’s past. As they encounter those who knew Maryla, it becomes clear that she touched countless people. Publicly speaking to new generations about her experience in the camps, Maryla strove to ensure that the horrors of the Holocaust would be neither forgotten nor repeated. The unexpected arrival of more than 100 hours of footage of Serena’s grandmother further enhances the portrait of Maryla, with the videos revealing her extraordinary personality, incredible strength, and inimitable sense of humor. Although a highly personal film, “Nana” also speaks to larger issues: the transgenerational weight of trauma and the necessity of Holocaust testimony continuing to be heard in the 21st century — a world where survivors are about to disappear and anti-Semitism and intolerance are on the rise.