Rick Grimes and Tyreese come out of the RV complaining about sleeping there again. Rick divides the group into jobs of cleaning up the prison, exploring the area around the gates to make sure it is secure, and looking after the children.
Andrea, Tyreese, and Rick lock themselves in the outer fence of the prison to clean out the zombies in the prison yard. At first they manage to clear it using only their melee weapons however more zombies come out of the prison doors and they need to defend themselves using their firearms. Andrea has to run back to Allen, who is outside the fence on watch on the roof of the RV, crying because the loss of his wife, Donna. Andrea reaches him and asks him to open the door. Inside the RV, Chris and Julie are babysitting Carl Grimes, Sophia, Billy and Ben. Chris starts complaining using insults and is told by Carl he shouldn't curse because he is still not an adult, but Carl only receives a rude answer. Sophia asks Carl if he wants to be her boyfriend while playing go fish, though he refuses. While patrolling along the fences, Lori and Carol are discussing how depressing life is at the moment and talk about if the prison will be perfect enough for a new life.
The trio manage to kill all of the zombies by having Andrea and Rick fire as Tyreese reloads the guns in case any more exit form inside of the prison.
That night Sophia complains she's still hungry but they don't have any food left; Rick says tomorrow they'll attempt to find the stockpile of canned food inside the prison, because if they are lucky it was overrun before it was looted. Allen sarcastically points out that "Hopefully it's just full of flesh eating monsters and our baked beans are still intact in there." While on watch on top of the RV, Rick and Tyreese discuss how safe the prison is and how they can't spend another night in Dale's RV.
The group is awoken by Lori Grimes running outside to throw up due to her morning sickness. The group is divided into groups; Rick and Tyreese will clear inside of the prison, Lori, Andrea and Allen clear the bodies while Dale covers them, and Julie and Chris must babysit again. While clearing the prison Rick and Tyreese encounter a closed door to the cafeteria which is barricaded with a police baton. When they burst in, they find four other survivors; Dexter, Andrew, Axel, and Thomas Richards.
The rest of the group gets inside the cafeteria where they eat for the first time in quite a while. Rick informs the survivors about what has happened to the world while they have been isolated and Dexter tells them what occurred in the prison during the initial outbreak a month ago. Contrary to what Rick thought, the four survivors are inmates, not guards. Lori angrily asks what they did to be put in prison; Dexter says murder, because he killed his ex-wife and her boyfriend; Andrew was a drug dealer; Axel was done armed robbery; Thomas Richards said "tax evasion". It is also implied that Dexter and Andrew are in a homosexual relationship. Then Dexter shows Rick and his group around the prison, they reveal they had to use the freezer as bathroom after the buckets were all filled with excrement.
While touring the prison, Dexter asks Rick if he is going to get a gun and asks why he should trust the group. Rick says that they haven't killed him yet, so he'll have to trust them. The group open the doors to the gym. Seeing it is full of zombies, they decide to "deal with it later". Then they go to the laundry room, the shower room, the garage with several prison buses, some police cruisers and some motorbikes still inside, then they go to the C-Block. While setting up their rooms inside the block, Rick proposes bringing the Greene Family to live with them, so they can grow food inside the fence and learn how to farm for a long-term life. Rick and Dale head to the farm in the RV. The group at the farm accepts Rick's offer and leave for the prison after they have collected their belongings because the farm was getting attacked more often, Otis stayed behind to watch over the farm and all the livestock.
Back at the prison, Rick and Lori discuss living with the prison inmates and Lori also has an awkward conversation with Carol about her baby. Hershel talks with Rick to apologize for nearly shooting him and thanks him for the great opportunity to start a new life at the prison.
The following night Chris and Julie are having sex then commit to shoot each other in a suicide pact. After hearing one shot, Rick runs to find Tyreese hugging his dead daughter's body and Chris saying they were supposed to kill each other at the same time. Julie turns and attempts to bite Tyreese, who attempts to reason with her to try and get her to not be dead anymore. Rick can't get a clean shot so Chris shoots her. Tyreese then chokes Chris to death in an insane rage and then continues to mutilate the animated corpse of Chris (off-panel). The next day, while burning their bodies, Rick is disconcerted by Tyreese because he showed no emotion whatsoever and smiling at him. While discussing it they realize that they don't need to be bitten for them to turn. Rick suddenly realizes that there is something that he needs to do. Rick informs Lori, Carl and the rest of the group that he will be gone a couple of days to do something.
Ricks returns to the Atlanta camp to kill the reanimated Shane. He tells zombie Shane that he was a good man and he regrets all that happened between them. Then Rick shoots Shane in the head, but doesn't rebury him.
Glenn and Maggie Greene start to explore the Prison, Glenn and Maggie stumble upon the barber shop in the prison where they have sex and cut each others hair. Glenn and Maggie return and Susie and Rachel, the twins, want go to and check it out so Maggie takes the twins to the barber shop.
Tyreese, Andrea, Billy Greene and Glenn head into the gym to clear it of all the zombies; however, after forming a plan to stay as a group and kill the zombies by moving out making sure no zombies get past them, Tyreese attacks the zombies suicidally and the rest are forced to leave him inside as he is swarmed.
Hershel starts to search for Rachel and Susie, he can't find them and he gets mad, he finally finds the barber shop, he opens the barber shop door and finds the decapitated heads of his twin daughters, Susie and Rachel Greene. Glenn shoots their heads and Dexter is "arrested" because everyone thinks Dexter is the murderer. When Rick returns back to the prison, he is informed about the death of Tyreese, Rick goes into the gym and find Tyreese sitting in the corner of the gym, having killed all the zombies. Andrew talks with Dexter in his cell about leading a mutiny by procuring the riot armory and arming themselves.
While Andrea is in the laundry she gets attacked by Thomas Richards, who is revealed to be the real killer. Andrea runs out into the open with Thomas in insane rage. Rick begins hitting Thomas to the point where he breaks his hand. Although Thomas didn't manage to kill Andrea, he did cut her on her left cheek and cut off her left earlobe. Rick introduces the new rule "You Kill You Die", though Lori objects to the capital punishment Rick has in mind with hanging Thomas. They lock Thomas in the fridge because of the smell but then he is taken away after Rick tells them he'll suffocate. Later Patricia frees him, but he attempts to kill her and is shot by Maggie. Hershel is the only one to watch as the zombies outside eat Thomas' dead body as a form of closure. Dexter, Andrew and a defecting Patricia use the guns from the armory to threaten Rick's group into leaving The Prison by telling them to "Get out of my house".
The story resumes with a mysterious woman with two chained up, armless and jawless zombies accompanying her, she hears gunshots and follows it. Outside is not far from the gates is Otis, he is heading for the prison after he had stayed behind at the Greene Family Farm to take care and manage the livestock, and only now decided to head for safety. He soon ends up surrounded by zombies. He is rescued by Michonne Hawthorne, the mysterious woman at the start, who helps Otis fight off the zombies.
Inside the prison yards, a horde of zombies pour out from Block A after Andrew forgot to close the prison doors after gaining weapons from the armory within. Dexter and the other survivors are forced to work together to wipe out the zombies. Rick Grimes waits for an opportunity and shoots Dexter in the head. When the battle ends, he claims Dexter must have caught a stray round. Tyreese saw the shot, but says nothing. Andrew runs off suicidally through the open prison gates without a word. Axel allies with the other survivors. The gates are then opened and Otis travels in stating that he was saved by Michonne, Michonne then asks if that has earned her a place to rest, Rick agrees but only is she was to hand over her weapon, which was a katana, and kill the two accompanying zombies.
While cleaning out the rest of the prison, Allen is bitten on the leg. Rick, Axel, Dale and Tyreese carry Allen out to the yard where Rick amputates Allen's infected leg, hoping to catch the infection in time, Hershel then shows up and helps by cutting some of Axel's horse-like hair to stop the bleeding. Hershel and the others finally start up the garden while Dale and Andrea promise Allen that they will take care of Ben and Billy for him.
Michonne seduces Tyreese, and Carol sees Michonne giving Tyreese a blow job and attempts suicide. Carol survives, and Rick confronts Tyreese, blaming him for Carol trying to kill herself. Tyreese announces that he saw Rick kill Dexter. The argument soon spirals out of control as they call the other one insane and the two fight, which ends after Rick mysteriously blacks out and falls over a railing. Andrea comes down to tell everyone that Allen has died either from the infection or from blood loss. Rick then shoots Allen, preventing reanimation, and while being confronted by Hershel and Michonne passes out once again. When he awakens, he learns that the entire group now knows about Dexter's murder. They have decided that the pressure of being their "leader" is beginning to cause him to crack, and they have made him merely one of four "co-leaders," with the others being Tyreese, Dale and Hershel. Rick meets with the others outside to explain his reasons for killing Dexter and that they are going to have to start acting like savages most of the time if they are to survive, and they will have to stop deluding themselves that society can ever be rebuilt the way it was. He finally screams out "You think we hide behind walls to protect us from the walking dead! Don't you get it!? WE ARE THE WALKING DEAD!"
- Julie (Alive and Zombified)
- Chris (Alive and Zombified)
- Susie Greene (Alive and Zombified)
- Rachel Greene (Alive and Zombified)
- Thomas Richards
- Shane (Zombified)
- Mike (Zombified)
- Terry (Zombified)