The Walking Dead takes place after the onset of a worldwide zombie apocalypse. The zombies, colloquially referred to as "walkers", shamble towards living humans and other creatures to eat them; they are attracted to noise, such as gunshots, and to different scents, e.g. humans. Humans that they bite or scratch become infected and slowly turn into walkers as well.
The series centers on sheriff's deputy Rick Grimes, who wakes up from a coma to discover this apocalypse. He becomes the leader of a group of survivors from the Atlanta, Georgia region as they attempt to sustain themselves and protect themselves not only against attacks by walkers but by other groups of survivors willing to assure their longevity by any means necessary.
Rick and the group leave Atlanta and encounter a threat on the highway the likes of which they've never seen. Elsewhere, the group search for a missing person.
Rick discovers a possible safe haven. Shane must go on a dangerous mission to get needed medical supplies.
The group desperately awaits Shane's return. Shane finds himself trapped in a school, surrounded by the undead. Daryl and Andrea search for someone in the woods.
Shane makes a deadly sacrifice which leads to unusual behavior and self-distancing. The rest of the group tries to hang on somewhere between living to die and dying to live.
Concerned for their safety, the group makes a plan – one that Hershel disagrees with adamantly. He makes it clear the group is fine to stay for now, but not indefinitely.
Secrets are told and secrets are revealed. Hershel refuses to acknowledge the world’s new reality. Andrea comes out of her shell. Everyone is becoming more and more aware that “everything is food for something.”
Hershel sets a deadline. All secrets are out in the open. Glenn stands up for himself and Shane takes charge.
Rick and the others try to restore order in the aftermath of a terrible discovery. Hershel takes up an old habit and disappears, Rick and Glenn must follow him into town.
Rick, Hershel and Glen are trapped and fight to survive; Shane finds Lori in danger.
Rick and Shane are in conflict over the fate of an outsider; Andrea helps Hershel's daughter face a crucial decision.
Rick sides with Shane causing Dale to worry that the group is losing its humanity; Carl's actions have unintended consequences.
Someone dangerous may be loose near the farm; Rick, Shane, Daryl and Glenn keep the group safe.