The history of genocide often defies our ordinary approaches to representation. The trauma is too extreme. But the moral imperative to document and fix in collective memory the Holocaust means that its myriad stories of suffering demand retelling. This seeming paradox raises questions about how we turn atrocity into narrative, questions at the heart of Meryl Frank’s “Unearthed: A Lost Actress, a Forbidden Book, and a Search for Life in the Shadow of the Holocaust.” The author, like many who have taken up the challenge of representing a dimension of the Holocaust, is a descendant of survivors, and she approaches...