Recently laid off, Jack Heart uses his time away from work to fulfill a lifelong dream: hiking the Appalachian Trail. In winter. After fighting off a sickly black bear, Jack decides to take a break from the Trail. However, he quickly realizes his problems are much greater than rogue wildlife. A toxic beef supply has turned millions of people into Heathens--flesh hungry corpses--and cities are putting themselves under quarantine. Hundreds of miles from home with no food and trapped by vigilantes, Jack Heart descends into a desperate, violent place in order to survive.