April 26th begins as a day far from normal for the three Canon brothers and their parents. Joel Canon, the eldest brother and a doctor, encounters a woman who seemingly revives from death into an enraged and cannibalistic state in Indiana. Amos Canon, a homicide detective, investigates a string of murders involving use of a blue poison in New York. Jonah Canon, a National Guardsman, has to return to his base for emergency deployment to Washington. Ezra and Ruth Canon, their parents, rush whatever they can into the impenetrable cellar of their home. Amos, with his partner Samuel, uncovers a vast act of internal terrorism from an informant who asks to only be named Paul. Paul recounts the story of the Descendant's of Dante, a fanatical religious group which ultimately connects the murders, poison, and their spreading impact across America. The crisis unfolds through the eyes of the Canon family, news reports, and presidential addresses. As Jonah struggles with his atheistic views, he and his team guard the White House, which has been turned into an impenetrable fortress. Joel tries to keep stability in a poorly staffed hospital amidst riots of confused, infected patients and mindless wraiths trying to get in. Amos, the only link to the information from Paul, tries desperately to end the crisis while also help his family. Throughout, the Canon family strives to hold onto the hope of a civilized world continuing and their own humanity amidst the growing epidemic, chaos, and questions of faith.