Months have passed since the group left Hershel's farm. With Lori in the latter stages of her pregnancy, the group is lucky to find an abandoned prison. They manage to clear it of walkers and take up residence, finding several prisoners, who have locked themselves inside. During a particularly bad walker attack, the group is separated. When Lori goes into labor, Maggie has to perform an emergency C-section, which kills Lori. Carl shoots her to prevent her from coming back from the dead.
Michonne and Andrea find a walled town called Woodbury. A seeming utopia safe from walkers. It's run by a man named The Governor, who initially treats them with mistrust, which is reciprocated in full by Michonne. They also find that Daryl's brother Merle is there, having survived amputating his own hand back in Atlanta.
We learn that Michonne's mistrust of The Governor is well-placed. He kills a group of soldiers for their equipment, keeps his walker daughter leashed to the wall, and has aquariums full of animated walker heads in his den. He hides all of this from Andrea as he pursues a relationship with her. When Michonne escapes, Merle tracks her down but is unable to kill her. She manages to get to a town, where she sees Merle capture Glenn and Maggie. Injured, Michonne gets to the prison and leads a group of them to Woodbury to save Glenn and Maggie.
In the fight that follows, Daryl is captured and Michonne kills The Governors daughter and stabs him in the eye, leaving him emotionally and physically ravaged.
Meanwhile, another group has managed to find the prison. Led by a man named Tyreese they are tired and helpless. A distrusting Carl allows them to stay but keeps them under lock and key until Rick can return.
As the first half of season 3 ends, an enraged Governor forces Daryl and Merle to fight one another for survival.
