At an internment camp in Indonesia, forty-seven people are pronounced dead with acute hemorrhagic fever. When epidemiologist Henry Parsons travels there on behalf of the World Health Organization to investigate, what he finds will have staggering repercussions. Halfway across the globe, the deputy director of U.S. Homeland Security scrambles to mount a response to the rapidly spreading pandemic leapfrogging around the world, which she believes may be the result of an act of biowarfare. And a rogue experimenter in man-made diseases is preparing his own terrifying solution. As already-fraying global relations begin to snap, the virus slashes across the United States, dismantling institutions and decimating the population. With his own wife and children facing diminishing odds of survival, Henry travels from Indonesia to Saudi Arabia to his home base at the CDC in Atlanta, searching for a cure and for the origins of this seemingly unknowable disease.