The pilot, based around the first 2 issues of The Walking Dead. For this opening episode, most of the focus would be on Rick Grimes, and his mostly solitary journey. You start with him getting shot, then waking from his coma. Then, we'd follow him through his escape from the hospital, and after the detour to his abandoned home where he meets Morgan and Duane Jones, we follow him on his journey to Atlanta, climaxing with the horrific reveal of the hellhole that city has become and his narrow escape from it. You end the episode with Glenn bringing him to the camp, where he finds his wife, Lori, and his son, Carl.
In this episode, we'd be introduced to the wider ensemble cast of the survivors living in the camp. So here the show would go from essentially being a one-man show to being an ensemble-driven show. Various character dynamics would be established, particularly the friendship between Rick and Shane, and the loving family network of Rick, Lori and Carl. We'd see some early skirmishes with zombies, including Glenn and Rick's nailbiting expedition into the city to find the gun store. You end the episode with the revelation that Lori and Shane slept together, and Shane is not to be trusted.
This is the episode where the camp set-up falls apart. We have the night-time attack on the camp, where Amy is killed and Jim is bitten, leading to him being left to die. And as a backdrop to this, you have Shane's descent into madness. The episode would of course end with that pivotal moment, where Shane is about to kill Rick, only for young Carl to shoot Shane and kill him.
Rick takes over as leader, and decides they are to leave the camp. This episode would focus on their struggles in the wilderness, fending off the odd zombie attack. We would also meet Tyreese, his daughter Julie, and her boyfriend Chris, as they encounter the group of survivors and join them. There would be a little switching around of the "two issues = one episode" formula here, as I think a good ending for the episode would be the issue 5 ending, with Lori revealing to Rick that she is pregnant.
This would be a goodun. The group discover the Wiltshire Estates gated community, and move into it, hoping to start a new life there. But it all goes horribly wrong when they discover the place had become a mass grave, and is now teeming with zombies. They barely escape with their lives, all except Donna, who is killed. Back on the road, Rick, Tyreese and Carl go hunting. You end the episode with Carl being shot and seemingly killed.
We discover that it was Otis who accidentally shot Carl, and that Carl is not dead, but wounded. Otis takes Rick and Carl to Hershel's farm, and Hershel treats the boy. The rest of the survivors show up at the farm, and Hershel introduces them to his family and allows them to stay while Carl recovers. Rick learns about Hershel collecting zombies and locking them up in his barn instead of killing them. They eventually break out, and two of Hershel's children are killed. Enraged by grief, he turns out Rick and the other survivors, and the episode ends with them stranded out in the wilderness once moe.
The survivors discover the prison, and set about trying to clear it of zombies, so they can live there. They find the four stranded prisoners holed up there, and they become part of the group. Rick goes back to Hershel's farm, and invites him and his remaining family to join them in the prison. At the end of the episode, Julie and Chris botch a suicide pact, with Chris killing Julie before she can kill him. Tyreese finds the sobbing Chris and his dead daughter, and while he's holding her dead body in his arms, she comes back to life as a zombie.
Once zombie Julie is killed, Tyreese strangles Chris to death, then takes grim satisfaction in mutiliating him once he comes back as a zombie. Learning that people come back as zombies after dying even when they haven't been bitten, Rick journeys back to the old camp to finish off zombie Shane. Back at the prison, meanwhile, we see Tyreese dealing with the intense trauma of what he has experienced. When clearing out the prison gym of zombies, he gets buried under a pile of them and the others have to leave him behind. When they return later, they discover him still alive, having bludgeoned every last one of them. At the end of the episode, Hershel discovers his twin daughters dead, their heads cut off. I found this to be the single most upsetting, horrifying thing I've read in the comic so far, and I don't know if this image would make it to TV. But it would be an incredibly powerful, horrifying conclusion if they could get away with it.
Now, following my formula, this would be the most packed episode of any this season, and as such if AMC decided to follow a 13-episode structure, this is the one episode I would split into 2 episodes to make up the number. Here, the survivors discover a killer is in their midst. Suspicion falls on convicted murderer Dexter, and he is locked up in a cell until they figure out what to do with him. However, the true killer turns out to be another convict, Thomas, who slashes Andrea across the face and attempts to kill her, before Rick stops him, beating him to a pulp in the process. The decision is made that he is to be executed, but before they can do it, he attempts escape, and is shot to death by Hershel's last remaining daughter, Maggie. The episode would end with a mini revolution, with Dexter and fellow convict Andrew holding the survivors at gunpoint and demanding they leave the prison, despite them facing certain death at the hands of the zombie masses awaiting outside.
We pick up from the previous week's cliffhanger, with Dexter's ultimatum interrupted by an influx of zombies from A-Block of the prison, which Dexter and Andrew breached while getting their guns. We then have a huge battle with the biggest wave of zombies seen at this point in the series. During the battle, two important things happen. First, we get the arrival of Michonne into the series, as she shows up with her samurai swords and proves to be a big help in the battle. Second, Rick shoots Dexter in the head during the chaos, passing it off as accidental crossfire - a defining moment for the character. Once things have calmed down and something resembling a status quo has been restored, a group of survivors set out to clear A-Block of its remaining zombies. In the process, Allen is bitten in the leg by one. After dragging him to safety, we end the episode with Rick hacking off Allen's leg with an axe in hopes of stopping the infection from spreading.
We see that Rick's plan to stop the infection worked, but Allen lost a lot of blood, and is near death anyway. This would be more of a quieter, character-driven episode, as we see how the various members of our shifting ensemble have adjusted to this new status quo. The key development would be Carol discovering that Tyreese has cheated on her with Michonne, resulting in her breaking up with him. The episode would end with Lori going to talk to Carol, only to discover she has slit her wrists.
When wanting to tell him the news about Carol, Rick walks in on Tyreese and Michonne kissing, and realises this is why they broke up, and now why Carol has attempted suicide. We have a massive argument between Rick and Tyreese, which escalates into a huge fight, where the two beat the hell out of each other. The fight ends when they learn that Allen has died. Rick shoots Allen's corpse in the head to prevent him coming back as a zombie, then passes out. While Rick is unconscious, the rest of the group decide that he is cracking under the pressure and should no longer be their leader. They decide that instead the survivors should be led by a committee of Rick, Tyreese, Glenn and Hershel. Maybe insert some action scene involving zombies that's not in the comics in here to make the finale seem more action-packed. Rick wakes up, and we end the series with his big speech to the rest of the group from the end of volume 4, culminating in his famous "We ARE the walking dead!" line. Fade out, end of series.