It is eight months since the events of the season three finale, and Rick's stronger group emerges.
The Governor and Martinez rush to find shelter for Shumpert as he has been bitten on the arm. The Governor cuts off the infected arm, and Miranda and Eliza nurse him back to health.
Carol and Daryl are now a couple, and share a kiss.
Carl is even darker now, and only talks to Judith.
The Governor's trio winds up running into the Morales family, who have been missing since Season 1.
Karen's son, Noah has an asthma attack, and a new doctor named Bob Stookey joins the group. He tends to Noah, and later begins a flirtation with Karen.
Michonne is now dating Tyreese, and is very good friends with Sasha, but is still traumatized over Andrea's death.
Maggie is six months pregnant with Glenn's baby, and they decide to elope. Hershel officiates, and Beth is the Maid of Honor, while Carol, Karen, Michonne, and Sasha are bridesmaids. Rick is the Best Man, while Daryl and Tyreese are groomsmen.
Rick now co-leads with Daryl, Glenn, and Hershel, and his conscience remains clear, as Lori is nowhere to be found, but sees Morales in the distance.
Not completely trusting the Woodbury group, Rick and his group clear another cellblock for them, but has Glenn, Hershel, and Sasha stay in that cellblock in order to keep an eye on them.
Bob flirts with Carol, but she turns him down, since she is with Daryl, and she is friends with Karen and doesn't want to betray her trust.
Maggie has several worries about her baby after what happened to Lori, but Beth comforts her.
Beth and Noah begin a romance, but under a watchful eye from Hershel and Karen.
Morales comes back to find The Governor raping Miranda, and attempts to get her away from him, but is shot by Martinez, paralyzing him. Eliza and Louis run to the prison, and asks Rick for help.
Michonne discusses her early life with Tyreese, and reveals that her father died of cancer before the outbreak began, and her mother got bit. Tyreese admitted that his parents died before the outbreak, and that Sasha is his younger sister.
Dr. Stevens arrives at The Governor's shelter, and nurses Morales. She scolds Martinez for shooting someone, and is shocked to learn that The Governor raped Miranda.
Rick arrives at the shelter with Daryl, Eliza, and Louis, and the only people now there are Dr. Stevens, Miranda, and Morales.
Carol and Maggie are on guard at the prison, and The Governor arrives. Maggie runs, and Carol stays to fight. The Governor flees after Martinez is shot in the arm by Carol.
Morgan Jones joins Rick's prison group, unloading all of the ammo he had in King County from a truck.
The Governor and Shumpert carry Martinez into King County, and enter the building Morgan was living in. They disassemble all of his booby traps, and lay Martinez on the cot.
Karen questions Rick, Daryl, Glenn, and Hershel's leadership as they keep letting people into the group. Carol reassures her, saying that we need all the strength and weapons we can get.
Beth and Carol help Maggie learn how to become a mother.
Glenn asks Rick for advice on parenting, but Rick says he should be talking to Hershel. Hershel gives Glenn confidence when he says that he trusts Glenn with his daughter, and he'll trust him with his grandchild.
Bob and Dr. Stevens' affair continues.
Michonne and Tyreese's relationship hits a rough patch when she won't open up to him.
Martinez wakes up, and tells The Governor he refuses to fight for him anymore. He flees King County.
Daryl plants a passionate kiss on Carol and says he loves her. She is shocked, but happy as well.
Eliza and Louis enjoy playing with Carl, and check on their dad. He is doing much better, and is talking. Miranda goes to visit him, and she tells him that she is pregnant, but it is The Governor's child.
Hershel's funeral is held. Rick has everyone go around and say a thing about him.
Glenn and Maggie share stories about him, as does Beth.
Noah comforts Beth throughout the funeral.
Michonne, Morgan, Sasha, and Tyreese express gratitude for Hershel and explained his kindness.
Carol and Carl talk about his great sense of humor. Carl is shown holding Judith, and standing next to Eliza and Louis.
Daryl and Rick talk about how he took them in on his farm.
Miranda and Morales said he was a good man for the short team they knew him.
Shumpert wakes up, still in Martinez's tent. Martinez has him handcuffed so he cannot escape. He convinces Shumpert that The Governor is no good, and will only get them killed, so they return don't return to King County, but take their chances in the forest.
Martinez will not stop bleeding, and Shumpert has no other choice but to put him down. Shumpert flees the forest, and returns to King County. He tells The Governor that Martinez was bitten by a walker, and he tried to attack Shumpert.
Shumpert comes across a building and they find tons of ammo. They decide to hit up the prison again, immediately.
Shumpert and The Governor drive through the prsion gates, and begin shooting the residents sitting outside. Beth, who is holding Judith, runs back into the prison while being shot at.
Carol runs outside, and shoots at them. She hits Shumpert in his good arm, and then takes shelter.
Karen runs out and helps defend the prison. The Governor shoots her in the leg, and Rick is forced to amputate her leg. Sasha and Tyreese help carry her back into the prison, and Noah watches in awe from the side. He dodges several bullets, and runs inside.
Daryl runs out and shoots Shumpert in the head with an arrow, killing him. Carol shoots his corpse in the head to prevent him from reanimating.
Dr. Stevens runs outside to help wounded patients, but The Governor captures her and takes her hostage. Carl shoots The Governor in the back of the head, but Dr. Stevens is still unable to free herself. The Governor reanimates and bites her. Bob runs up and shoots them both in the head, apologizing.
Glenn, Maggie, and Michonne emerge from the bushes and rush out to grab Carol and run back inside.
The group decides to flee the prison and go elsewhere. The final scene depicts them driving away from the prison, not knowing where to go next. Morgan is shown smiling next to Michonne, Tyreese, and Sasha. Morales is shown with his family, Rick is shown driving with Carl, Carol, Daryl, Judith, and Beth. Glenn, Maggie, Bob, Noah, and a wounded Karen are shown driving away from the bus, along with the other Woodbury residents who joined the group in the Season 3 finale.