Documentary filmmaker Roberta Grossman is obsessed with the Holocaust, always has been. Its ever-present evil—the ultimate “rift in humanity,” she says—just won’t let go. “It’s not that I can’t pull away from it, but rather why others can.” So she asserts on the phone from her home in Los Angeles. Producer Nancy Spielberg (yes, Steven’s sister), with whom Grossman collaborated on the Holocaust documentary Who Will Write Our History, is participating in the conversation from her New York home. Their film, which has already been screened at various festivals worldwide, will make its television debut on the Discovery Channel on January 26 at 3 p.m. The telecast is part of Holocaust Remembrance Day commemorations. It’s also the 75th anniversary of the liberation of Auschwitz.