It takes place after the onset of a worldwide zombie apocalypse. The zombies, referred to as "walkers", shamble towards living humans and other creatures to eat them. They are attracted to noise and to scents, including the scent of humans. Humans who are bitten or scratched by walkers die and become walkers themselves. Early in the series, it is suggested that, because any human who dies will reanimate as a walker regardless of cause of death, all living humans carry a pathogen responsible for the mutation that turns humans into walkers. No pathogen is ever confirmed, however. The mutation is activated after the death of the host. The only way to permanently kill a walker is to damage its brain or to destroy the body entirely (e.g. via cremation).
Initially, the series centers on sheriff's deputy Rick Grimes, who wakes up from a coma in the first episode of the series. While Rick was comatose, the world was taken over by walkers. Rick becomes the leader of a group of survivors from the Atlanta, Georgia region who attempt to sustain and protect themselves against attacks by walkers and against other groups of survivors willing to use any means necessary to stay alive.
When sheriff's deputy Rick Grimes of King County, Georgia, wakes from a coma, he discovers the world has been overrun by zombies ("walkers"). Rick befriends Morgan Jones and travels alone to Atlanta before finding his wife Lori, son Carl, and his police partner and best friend Shane Walsh in the woods with other survivors. After being attacked by walkers at night, the whole group travels back to Atlanta to the Centers for Disease Control (CDC) building, but find from the sole remaining scientist that no cure yet exists for the pandemic.
Season 2[]
Rick's group, searching for Carol's missing daughter, Sophia, takes shelter at a farm run by Hershel Greene. Tensions with Hershel's family worsen after it is discovered that he has a barn full of walkers: former friends and family members. Rick learns that Shane and Lori were romantically involved while he was in a coma, and that Lori is pregnant. Shane and Rick's friendship deteriorates, until Rick is forced to kill Shane in self-defense. The commotion attracts walkers to the farm, forcing Rick's group and Hershel's family to evacuate.
Season 3[]
Eight months after fleeing the farm, Rick's group—sans Andrea—finds a remote prison, which they make their new home after clearing it of walkers. Lori dies from an emergency C section, and Rick starts to become unhinged and hallucinate. Andrea was rescued by Michonne and the two discover Woodbury, a fortified town led by a deceitful man known as "the Governor" who seeks to destroy the group at the prison. Conflict erupts between the two groups leading to the fall of Woodbury, but the Governor kills Andrea and escapes. The remaining citizens of Woodbury move into the prison.
Season 4[]
Several months after the Governor's attack, a deadly flu kills many of the people at the prison. The Governor finds Martinez, his former right-hand man and kills him, taking over his group before leading them into the prison. Rick's group is forced to separate and flee, while Hershel and the Governor are killed. The scattered survivors try to find each other and make new acquaintances. They all find numerous signs pointing to a safe haven called Terminus. Group by group, they reunite at Terminus, but Rick's group, sans Carol, is captured for an unknown purpose.
Season 5[]
The residents of Terminus have become cannibals. Carol leads a charge that frees Rick's group. Some of the group are captured by a group of corrupt cops based out of Grady Memorial Hospital. After the group migrates to Virginia, a stranger named Aaron approaches, inviting them to join the fortified community of Alexandria, led by Deanna Monroe. They quickly realize the residents are ill-prepared to do what it takes to survive. Rick becomes attracted to Jessie Anderson and discovers she has an abusive husband. Deanna orders Rick to execute the man after he kills her husband as Morgan arrives unexpectedly.
Season 6[]
Deanna gives Rick command of Alexandria to protect the town. A group known as the Wolves use a zombie horde to attack Alexandria, and Deanna and the entire Anderson family (among others) are killed. While recovering, Alexandria learns of a community called the Hilltop. Paul "Jesus" Rovia invites them to trade supplies with Hilltop if they can help end the threat of the extortionist Saviors led by a man named Negan. Although Rick's group decimate one Savior outpost, they are later caught by Negan and forced to submit to him.
Season 7[]
Negan brutally murders Abraham and Glenn, initiating his rule over Alexandria. His actions initially lead Rick to submit, but Michonne persuades him to fight back. They encounter a community called the Scavengers and ask them for help. Carol and Morgan befriend King Ezekiel, the leader of the Kingdom, while Maggie and Sasha rally the Hilltop. Rosita and Eugene make a bullet to kill Negan. When the bullet is blocked by Lucille, Negan's baseball bat, Negan forcefully recruits Eugene as a Savior. The Saviors and turncoat Scavengers attack Alexandria but are repelled by Sasha's sacrifice and the aid of Kingdom and Hilltop soldiers.
Season 8[]
Rick, Maggie, and Ezekiel rally their communities into war against Negan and the Saviors. Losses are heavy on both sides and many of the Kingdom's soldiers are killed. Alexandria falls to a Savior attack, and Carl is bitten by a walker. Before euthanizing himself, Carl convinces Rick to end the war peacefully and restart society anew. Negan attempts to wipe out Rick and his allies in a final battle, but Eugene thwarts his plan by sabotaging the Saviors' bullets. Rick wounds Negan, but against Maggie's wishes, spares and imprisons Negan, ending the war.
Season 9[]
Eighteen months after Negan's downfall, Rick proposes building a bridge to ease trading, but this leads to more resentment. Rick is seemingly killed when he destroys the bridge to prevent an invasion of walkers. Six years later, his absence has caused estrangement between the communities, and a new walker-controlling threat called the Whisperers demand the survivors do not trespass in their territory. Their leader, Alpha, has acquired a large horde of walkers that she will unleash if they do so. After her daughter Lydia abandons her mother's group for the Kingdom's, Alpha disowns her and massacres many residents during a fair.
Season 10[]
Alpha begins breaking down the communities with seemingly random walker attacks and acts of sabotage. Under Carol's orders, Negan infiltrates the Whisperers and assassinates Alpha. Her right-hand man Beta takes command of the Whisperers, but he and the horde are defeated by the survivors. Eugene leads a group to West Virginia to meet a new group of survivors. Meanwhile, Michonne travels north to search for Rick after finding evidence he survived his apparent death.
Season 11[]
Eugene's group convinces the Commonwealth, a large, prosperous community with a strict class system, to lend aid and refuge to the Coalition. However, autocratic governor Pamela Milton becomes hostile toward the Coalition after her corruption is exposed and her son Sebastian is killed. The Coalition leads a revolution against Pamela when she tries to sacrifice the lower classes to a horde containing more intelligent walker variants; in the aftermath, Rosita dies of a bite, Negan is accepted by Maggie as an ally, and Ezekiel takes over as governor. After the Coalition is rebuilt, Daryl leaves to find others.
