Last time around, it ended with The Governor taking out a number of his own people, who had run away with their collective tails between their legs.
This time, the bad guys have a tank.
How does it go down? Well...
The episode begins with The Governor trying to sell his new camp on the idea of taking the prison; he claims the people who live there are terrible people--that they mutilated him and killed his daughter. The talk is intercut with the shot of The Governor watching Rick, Carl, Hershel and Michonne outside of the prison gates, and of Rick's group setting fire to a pile of bodies.
On the way back from burning the bodies, before they get back into the gates, The Governor knocks out Michonne from behind a tree and takes Hershel and Michonne hostage; he tells the group this, and promises no casualties if they take the prison using them as leverage.
Everyone agrees to join up--except Lily, who comes to The Governor after the speech, saying that she doesn't like the idea of killing people--that she'd already told him they didn't need to fight for a new place. He tells her that he loves her--and that she needs to pack up, too.
In his camper, The Governor has Hershel and Michonne tied up; he cleans their sounds and gives them some food, telling them that it's going to be a long day. He tells Hershel that nobody is going to hurt them; Hershel doesn't believe him and wants to know what's going on. The Governor tells Michonne that he's come to accept that Penny was dead when Michonne took her out; that he has no desire to hurt anyone and he just wants the prison. Hershel tries to convince him that the two groups can share the prison if he's serious about that, but The Governor thinks that's not realistic; he'll never be able to live together with Rick and Michonne.
Hershel reminds him that his willingness to kill to take the prison means he's willing to kill Hershel's daughters; he asks how he can be willing to do that, if he knows the pain of losing a daughter, and The Governor tells him because Maggie and Beth aren't his daughters.
Half an hour later, everyone is headed to the prison and The Governor drops Lily and Meghan off at the side of the river, telling her that walkers can't make it through the water and so they'll be safe waiting there for him while he's at the prison. She still objects to trying to take the prison but he tells her that it's so they can survive--anywhere really safe will have people there; He approaches Meghan to get a hug before he goes.
Back in the prison, Glenn is half-awake in a cell with Maggie watching over him; he jokes about taking an anniversary vacation and Maggie tells him about a place Hershel took her as a child. She tells him she's going to get him some water, and he says he can do it--but she says she will anyway.
Daryl is angry with Rick about expelling Carol; Rick is defending his actions, but it's making little headway. Daryl asks what to do about the two girls Carol had been taking care of, and Rick says he promised her they'd be looked after.. Rick hasn't yet told Tyreese that Carol was responsible for the killings; Daryl says he'll come with him and see how Tyreese takes it.
In his cell, Bob is brooding over a shoebox when Sasha shows up. She thanks him for helping Hershel save her life; he tries to object but she doesn't want to hear about it. He tries to chase him through the prison to talk to him when he leaves, but starts to get weak and leans against the wall for support.
Rick and Daryl come upon Tyreese in the Tombs and he tells them their news will have to wait; that there's something they need to see. He leads them to a room where there's a dissected rat nailed to a board. He tells them he believes it's the same person who killed Karen; that they have to find out who. Rick starts to tell him it's not the same person, but before he can elaborate, there's a blast that shakes the ceiling above them.
The survivors (those who can) run to the fences, where they see The Governor's party--a line of cars flanking a tank. The Governor summons Rick down to talk. Rick starts to decline, saying he has to confer with the council, and The Governor brings out Hershel and Michonne. He tells Rick that he's making the decisions today.
Daryl, Tyreese and Sasha starts to formulate an evacuation plan, even though they're low on supplies and their numbers have shrunk due to the plague.
Rick and Daryl exchange looks and Rick tells Carl something before he goes down to see The Governor. The Governor gives him until sundown to clear out of the prison, and while Rick objects that there are sick people inside who won't survive the trek, including children, The Governor stands firm.
Daryl and Bob stand at the fence line, handing out guns and watching The Governor.
Down on the water line, Meghan is digging in the mud when Lily sees a walker making its way across the river. She prepares herself to shoot it and Meghan is trying to pull away a metal object embedded in the ground. The walker falls in the water and is carried away, and Lily puts her gun in her waistband. Meghan picks up the piece of metal--it's a sign that says "Warning: Flash flood area." In the mud below her, a walker starts working its way to the surface, grabbing her. Before Lily can get there, Meghan is bitten.
Back at the prison, The Governor continues to act like he's being benevolent by allowing Rick's people the opportunity to leave without combat; walkers start making their way to him and he shoots two of them, saying that the noise will draw more, so the longer they wait, the harder it will be for Rick and company to get out of the prison.
Atop the hill, Daryl and Carl are watching the action; Carl thinks he can kill the Governor from here, but Daryl tells him not to. The kids are starting to work their way toward the bus, holding baby Judith in her car seat, but Lizzie convinces them to get guns and help.
Rick tries to convince The Governor to live with them rather than expelling them. The Governor refuses, saying it's impossible. Rick tells him that they're not leaving--that if The Governor wants to take the prison by force, the survivors will fight back, the noise will attract walkers, the fences will fall and no one will have the prison. The Governor responds by taking out Michonne's sword and holding it to Hershel's throat.
Rick appeals to the rest of the Governor's group, telling them that nothing is stopping them from simply walking in the gates and joining the community without bloodshed. He delivers a stirring appeal to the group, and you can see that Hershel is pleased and proud to have Rick back to sanity. Unsurprisingly, The Governor responds by calling him a liar and chopping at Hershel. Gunshots begin; Rick wings The Governor's arm, takes cover behind the overturned bus from last season and it's generally pandemonium. Michonne finds her way around to the back of The Governor's group where she manages to free her hands from the ropes.
Hershel, too, is crawling away with the last of his life, but The Governor follows him and finishes cutting his head off. Tara drops her gun, unwilling to participate. Lily shows up carrying the body of Meghan, which The Governor takes from her and shoots in the head so that she doesn't turn.
Tara's girlfriend tells her it's too late to turn back; that Tara should run and find safe cover, and that she'll find her after everything is all over. The Governor tells his group to charge the wall with the tank, get in their cars and "kill them all."
The tank easily takes down the fence and Rick's people begin heading back toward cover. The Governor's group take significant losses, but Rick's people start having to head back to reload. The tank blows a hole in the building. The Governor takes cover behind the overturned bus while the rest of his people advance on the prison, presumably hanging back to minimize his risk.
Maggie is heading into the prison to get Glenn and tells Beth to get people on the bus and go without her if she needs to.
Rick leaps out from around the bus and tackles The Governor, punching the hell out of him. Inside, Beth rescues Glenn just as a tank shell takes out a piece of the wall. Rick and The Governor continue to fight while the tank finally rumbles to a stop and Tyreese takes out a few of The Governor's people around it. They're firing on him in large numbers, though. Maggie and Glenn get on the bus; Beth has gone to get Judith. Glenn is too weak to follow when Maggie goes looking for her sister. Daryl is being stalked by walkers. The Governor has the upper hand on Rick. Everything is going to hell.
Walkers start to hear what's going on and approach The Governor's people from everywhere. Daryl uses a walker as a shield to get closer to The Governor's people and throws a grenade under the tank, clearing out those nearby. Bob Stookey takes a bullet, but it's a through and through and he's confident he'll be okay. The bus leaves, leaving Maggie, Sasha and Bob trapped. Tyreese is cornered behind some potted plants but the two attackers who have him--including Tara's girlfriend--are killed by Lizzie. He tells them they have to get out of here, with walkers starting to circle, but they head off in the wrong direction and he's forced to follow.
The Governor is strangling Rick, about to kill him, when he's run through by Michonnne's sword. Rick asks about Carl; Michonne doesn't know where he is. Rick starts heading up to the building and Michonne circles back, looking down at the Governor but leaving him for dead instead of finishing him off.
Daryl gets a second grenade into the tank, forcing the rest of The Governor's people away, and then he kills The Governor's second-in-command Mitch with a crossbow bolt. Beth finds him, and he tells her that they need to go. Rick stumbles up to the building, shouting for Carl, but finds only walkers--until Carl takes them out from behind. The pair hug, and Rick asks where Judith is. Carl doesn't know.
It seems, at this point, that all of The Governos' people are dead. Judith is gone from her car seat, a bloody smear left where she was. Carl kills the next walker he sees and just keeps shooting until Rick stops him.
In the field, The Governor comes to, and Lily is standing over him. She kills him with his own gun. A parade of walkers rumble through the area, crushing the chess piece with the eye patch that Meghan had made for him. In the woods, Rick tells Carl not to walk back--just to keep walking.