Escaping the blazing inferno that was the CDC, the group heads out for the nearest military base only to be waylaid by a sea of abandoned cars on the Interstate. When walkers attack, Carol's daughter Sophia runs into the forest. While the group searches for Sophia, Carl is shot by a hunter named Otis. Luckily, Otis's boss is a veterinarian, Hershel. The group moves to Hershel's farm and continues to search for Sophia, led by an impassioned Daryl Dixon.
Tensions between Rick's group and the people living on the farm grow, as Hershel does not want them staying there. Lori finds out she's pregnant, but is unsure if the father is Rick or Shane. Her pregnancy increases Rick's desire to stay on the farm. It all comes to a head when Glenn (who helped Rick escape Atlanta) finds that the barn is full of walkers. After a heated debate between Shane and Hershel, Shane releases the walkers from the barn to be put down. It's here that the group finds Sophia, now a walker herself. Rick does what he has to, and shoots her in the head.
A distraught Hershel (a recovering alcoholic) heads to an abandoned tavern to drink. Glenn (now in a relationship with Hershel's daughter Maggie) and Rick go to retrieve him. It's here they run into an untrustworthy group of scavengers. After a shoot out, they bring a wounded scavenger, Randall, with them back to the farm. As he heals, Dale is attacked by a walker. Daryl is forced to kill him. The group wonders how they can ever trust Randall enough to let him go. Shane settles the issue by taking him into the field and breaking his neck. He hides this fact, and uses Randall's disappearance as a lure to get Rick alone and away from the farm. In the ensuing confrontation Rick stabs Shane to death. When Shane's corpse reanimates, Carl shoots him down.
The gunshot draws in all surrounding walkers, who swarm the farm. The group barely escapes, getting separated from Andrea, who has been with the group since Atlanta. As Andrea struggles to survive on her own, she's rescued by a woman with a samurai sword and two unarmed (literally) walkers on chains. As Rick's group makes camp, Rick reveals that he learned at the CDC that everyone is infected by the virus, they will all become walkers when they die. As the camera pans out, we see a large prison in the distance.
