When human extinctions occur in South America and spread worldwide, paleobiologist and genetic researcher Mark Freedman senses a connection to the Chromatium Omri bacteria, the oldest known life form on Earth linked to previous extinctions. The growing virulence in the "kill zones" spurs Freedman to join forces with Kathy Morrison, expert on viral and bacterial pathogens with the Centers for Disease Control. Despite personal losses, Freedman and Morrison find romance and make discoveries about the devastation and what lies behind it. Other colorful characters include dedicated policewoman Sarah Mayfair, whose horrific dreams and improbable survival enable contact with the forces behind the outbreaks; cynical Gen. James McKafferty, committed to preserving the U.S. at whatever cost; and Artie Hartman, goaded by his wife's death to wage war on gangs and government forces indiscriminately. The seemingly random attacks and emergence of chaos allow Bohacz to explore such themes as whether humanity deserves to survive, the meaning of being human, and the cost of perfect health and immortality. The originality of Bohacz's ideas is nearly equaled by detailed descriptions of a decontamination lab, the frenzied search for answers, and the aftermath of destruction. His vision of a humanity that faces the need to evolve profoundly or face certain destruction is as timely as today's news and as chilling a doomsday scenario as any ecological catastrophe can suggest.