This game is amazing in the detail department. However, I got mad at it 2 years ago, because some of the objectives were solid. It's a very good game, but I don't think Sony are interested in developing a sequel.
The story concerns a biker called Deacon, during a pandemic. You use a motorcycle to traverse the countryside, assisting your friends in these different camps. Like little fortresses, really. And you eventually locate this guy's wife, who is helping these soldiers on an island. Sometimes, you get interesting missions to do, like gathering up lavender to treat an injured companion, or spying on a research team by hiding in the bushes.
These infected things called Freakers move around in hordes. But you get a lot of human opponents too, plus wild animals such as bears, wolves and crows.