Some time after being shot on duty, Deputy Sheriff Rick Grimes awakens in hospital to find it deserted with bodies strewn everywhere. He returns to his home to find it abandoned but believes his wife and son may still be alive. He meets Morgan Jones and his son Duane who explain to him that the world has been overrun with zombies (aka walkers). The disease usually started with an infection and high fever followed by re-animation. The creatures are attracted to sound and eat flesh to survive. Morgan tells him that he thinks there is a refugee center in Atlanta and Rick sets off in the hope of finding his wife and child. Once there, he finds himself surrounded by the undead with little apparent hope of escaping.....until he hears a voice over the radio.