In the early days of photography in the death-strewn wake of the Civil War one man seized America's 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 including Mary Todd Lincoln who arrived at his studio in disguise amidst rumors of seances in the White House. 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. It took a circus-like trial of Mumler on fraud charges starring P.T. Barnum for the prosecution to expose a fault line of doubt and manipulation. And even then the judge sided with the defense-nobody ever solved the mystery of his spirit photography. This forgotten puzzle offers a vivid snapshot of America at a crossroads in its history a nation in thrall to new technology while clinging desperately to belief.