As chief of investigative research at the Justice Department’s Oce of Special Investigations in the 1980s, David G. Marwell worked on the Mengele case, interviewing his victims, visiting the scenes of his crimes, and ultimately holding his bones in his hands. Drawing on his own experience as well as new scholarship and sources, Dr. Marwell will describe Mengele’s life and career, with specific focus on his wartime service both in frontline combat and at Auschwitz, where his “selections” sent innumerable innocents to their deaths, and his “scientific” pursuits—including his studies of twins and eye color — traumatized or killed countless more.