The group is stopped in a massive traffic blockage on their way out of Atlanta, and must avoid a large group of Walkers passing through. Sophie is lost in the woods after being chased by a pair of Walkers.
A desperate Rick finds a farm with a surgeon who might be able to save his son's life, but Shane must undertake a dangerous mission to find the right equipment. Meanwhile, the others debate whether to give up the search for Sophie or allow the group to be split.
Shane and Otis fight to escape from a horde of walkers at the local school, as Carl lays near death in need of the medical supplies they have. Glenn and T-Dog arrive at the farm, and Daryl and Andrea search the woods at night.
Shane struggles with his recent actions while Daryl redoubles his efforts to find Sophie. A new problem emerges on the farm when the group finds a walker trapped in a well.
Daryl finds a hopeful sign in the forest, but is on his own after being badly injured. Rick questions whether he is making decisions in the best interests of the group, and Glenn and Maggie consider the nature of their new relationship.
Glenn struggles to keep what he knows to himself, and Dale takes it upon himself to confront Hershel about what's in the barn. Rick and Shane take a group out for shooting practice, leading to some on-the-job advanced training for Andrea.
Glenn lets the rest of his friends know the secret of the barn, and Rick pressures Hershel to allow his people to stay on the farm. Shane considers his own strategy to secure the group's future.
After the shooting the group buries their dead, while Hershel retreats to grieve in his own way. Rick, Glenn, and Hershel encounter a pair of survivors, and Lori puts herself in danger by trying to find them.
As night falls, Rick, Glenn, and Hershel are pinned down in the bar by an armed search party. Shane goes in search of Lori, who must survive on her own after a car accident.
Rick and Shane attempt to leave their new visitor at a distance from the farm, but the trip becomes a desperate fight for survival. Lori discovers that Hershel's youngest daughter is facing a personal crisis.
Dale attempts to sway the group with a moral argument after Rick makes it clear that he plans to execute their prisoner. Carl gets too close to a walker in the forest, which has unforeseen consequences.
The group mourns a loss while working to shore-up the farm's security, and Carl makes a confession to Shane. Shane takes Randall's fate into his own hands, prompting a dangerous midnight search.
Rick and Carl seek shelter as the farm is besieged by a huge herd of walkers, and the group is fractured. Andrea fights to survive alone in the woods, and a revelation causes the group to question Rick's leadership.
