The following event begins in Pennsylvania, following an outbreak of the so-called Green Flu, a highly contagious virus whose symptoms include significantly increased aggression and the loss of many higher brain functions within its victim. Two weeks after the start of the epidemic, four immune individuals; Bill, Zoey, Francis and Louis are in Fairfield, where Bill discovers the remains of an unusual Infected, signifying that they are evolving.

The Survivors find themselves on a rooftop of an obliterated apartment complex, deep in the heart of the once-thriving metropolis of Fairfield-now completely overrun with hordes of Infected. A voice froma fullhorn calls out from a rescue helicopter.

The Survivors guide their way out of the downtown core of Newburg's business district, through derelict office floors and still-inhabited cubicles, and out onto the runway of Metro National Airport, where the only thing standing between them and the last plane out of the city is a murderous army of the undead.

Zombies lurk behind every tree, over every hilltop and behind every shadow in this terrifying moonlit search for a rumored evacuation zone to the north: several acres of back-country farmland taken over by the military to get the last of humanity out of Ground Zero. Plunge through pitch-black forests, stumble blindly through fields of swaying corn, and take aim at the silhouettes leaping at you from the darkness-all towards finding a hold-out that might already have been abandoned to the horde.