Nature is unpredictable, as are viruses; when one so volatile surfaces with a vengeance, there is little time to comprehend the devastation and even less time to do anything about it.

In the wake of the virus, there are three types of people: those immediately infected, those who are vulnerable, and those who are immune.

The initial infection ripples across the globe infecting half of the world's population. A small fraction of the ill are fortunate and die quickly from the disease. The remainder are condemned to a living death on earth.

The virus turns the infected into mindless and violent beings, intent on the kill and spreading the infection to those who are not immune.

One bite, one scratch.

The virus is an anomaly. It moves too quickly for a cure.

The world quickly transforms into a darkened place, besieged with violence and sickness. Hope against extinction is in the hands of the immune. They can walk freely among the infected and fight to extinguish them, while protecting those who are still at risk.

Archaeologist Grace Howard is one of the immune. While she dreams of traveling the world, learning about lost civilizations, the reality of being a wife and mother kept her saddled to a local job at the museum dusting dinosaur bones and relics.

Grace finds herself with a small group of survivors, some immune, some not. Together, they must struggle to live day to day in a dangerous world, while protecting those who can still fall prey to the infected. They must decide what is best - fight it out or hide until eventually and hopefully, the virus runs its course.