Mary Ellen joined the CIA when she was 23, dreaming of a life of glory and intrigue. Instead she got the graveyard shift, buried in the bowels of Langley sorting through an endless stream of surveillance photos and blurry satellite images. Then late one evening, another dinner date canceled, she discovers an awful truth. The CIA, the United States, likely the entire globe, is about to be brought to its knees by the greatest threat of the modern world;...