Reunited with his brother David, former Army Ranger Jack Smith begins to fortify a network of survivors in a world plagued by a viral epidemic that turns humans into flesh eating monsters. Over time, the once slow, zombie-like creatures become stronger, faster, and, apparently, smarter. A young man named Luke, who travelled with David's group on the journey from Cleveland to Indiana, seems to have a sixth sense about these "hunters," and this ability makes him an especially valuable ally in humanity's war against the infected. While medieval weaponry and modern armor remain the most effective defense when facing the creatures in combat, Jack and his allies learn that there are even deadlier enemies lurking beyond the battlefield.