Idriss Gabel and Marie Calvas, grandchildren of the last chaplain of Rudolf Hess at Spandau Prison, a high-ranking Nazi official, close friend, and right-hand man of Adolf Hitler, explore in this documentary film the unique relationship their grandfather, Charles Gabel, had with this prisoner who was sentenced to life imprisonment. Hess was the sole inmate of the vast Spandau Prison in Berlin, Germany, during the Cold War. For nearly ten years, Charles Gabel was the only person allowed to be alone with him during each visit, listening to his confessions, making him a privileged witness to history. The film raises a crucial and universal question, one that the chaplain himself must have faced: Can one show love, humanize the relationship, accompany, and grant forgiveness to one of the worst criminals in history?