In the early days of photography, in the death-strewn wake of the Civil War, one man seized Americas imagination. A “spirit photographer,” William Mumler took portrait photographs that featured the ghostly presence of a lost loved one alongside the living subject. Mumler was a sensation: The affluent and influential came calling. Peter Manseau brilliantly captures a nation wracked with grief and hungry for proof of the existence of ghosts and for contact with their dead husbands and sons.