Aliens have destroyed all major cities. They have not been seen yet - only their spaceships. The cities are overrun with humans and animals mutated by the extraterrestrial viral bombing.
A convoy of survivors has escaped Chicago and is heading south into the central states. They have just reached Kansas City, where two other survivors are trapped in the ruins of a collapsed shed.
And in time, as they travel west, they will stumble upon a farming community known as Gentry - a rural settlement that has survived the alien attack...