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 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.