When a man escapes from a biological testing facility, he sets in motion a deadly domino effect, spreading a mutated strain of the flu that will wipe out 99 percent of humanity within a few weeks. The survivors who remain are scared, bewildered, and in need of a leader. Two emerge—Mother Abagail, the benevolent 108-year-old woman who urges them to build a community in Boulder, Colorado; and Randall Flagg, the nefarious “Dark Man,” who delights in chaos and violence.