A single photograph--an exceptionally rare "action shot" documenting the horrific murder of a Jewish family--drives a riveting forensic investigation by a gifted Holocaust scholar.

In 2009, the acclaimed author of Hitler's Furies was shown a photograph just brought to the United States Holocaust Memorial Museum. The documentation of the Holocaust is vast, but there are virtually no images of a Jewish family at the actual moment of murder, in this case by German officials and Ukrainian collaborators. A Ukrainian shooter's rifle is inches from a woman's head, obscured in a cloud of smoke. The woman is bending forward, holding the hand of a barefoot boy. And--only one of the shocking revelations of Wendy Lower's brilliant ten-year investigation of this image--the photograph reveals the shins of another child, slipping from the woman's lap.

Wendy Lower's gripping detective work--in Ukraine, Germany, Slovakia, Israel, and the United States--recovers astonishing layers of detail concerning the open-air massacres in Ukraine. The identities of the victims, of the killers--and, remarkably, of the photographer who openly took the picture, as a secret act of resistance--are dramatically uncovered. Finally, in the hands of this exceptional scholar, a single image unlocks a new understanding of the place of the family unit in the history and aftermath of Nazi genocide.