|In the early 21st century, more than half of the world's population was wiped out in the zombie war. Millions dead (or worse) in only the span of a few years. It was a war the world very nearly lost. But the human race is resilient, and governments banded together to reclaim their lands. Slowly, over the course of decades, order was restored. But such horrible times are not easily forgotten. Even as new generations were born - those who had never had to live in fear of the zombies - the United States government was still living defensively.
The cities they began building had many names. Safe Havens. Repopulation Zones. Last resorts. Entire cities, enclosed entirely by steel walls. Nothing could get in... but nothing could get out, either. If there was ever a second war, people could be kept safe here.
They could never forsee that the second zombie war would start inside the walls, turning the safety zone into a prison...