Showrunner Scott M. Gimple talks with THR about why the AMC zombie drama has yet to be renewed, how that upcoming exit will service the story and the show's long-term plan.

[Warning: This story contains major spoilers from episode 808, "How It's Gotta Be," of AMC's The Walking Dead.]

The Walking Dead showrunner Scott M. Gimple wants diehard viewers of the AMC zombie drama — and comic book fanboys — to know that the game-changing death featured in Sunday's midseason finale will serve a much larger purpose on the series.

The final episode of 2017 ended with the unthinkable: Carl Grimes (Chandler Riggs), Rick's bad-ass teenage son, was bitten on the ribs by a walker trying to save a stranger and is dying. "It's all having to do with the greater story of the season," Gimple, who was the architect of Carl's death, tells The Hollywood Reporter. "It will be very apparent, the relationship of this awful incident — this very intense story turn — to the greater story."

In the larger sense, Riggs — who spoke exclusively with THR — confirmed that he is indeed exiting the show, with The Walking Dead's Feb. 25 midseason premiere serving as his last episode as Carl will take his final breath. Outside of killing off central character Rick (star Andrew Lincoln), Carl's death is by far the biggest change from creator Robert Kirkman's comic book series that serves as inspiration for the AMC drama. In the comic series, about 75 issues beyond where the show is, Carl is very much alive and well and — as he was on the show until Sunday's episode — seen as Rick's heir apparent. (Star Lincoln told THR that he, too, always thought Carl would inherit Rick's boots and revolver down the line on the show.)

Below, Gimple talks with THR about his decision to kill off Carl, why the show — one of the biggest hits on TV — has yet to be renewed for season nine as well as the long-term plan for both leading man Lincoln (whose contract is up this season) and the series itself.

The show hasn't been renewed for season nine yet. Given the game-changing nature of Carl's death, is there any discussion that season nine could be the end?

We're juggling a lot of things, but there's been no discussion about season nine being the end.

Is there a long-term plan in place, especially after Robert Kirkman signed an overall deal with Amazon Studios?

There's always been a long-term plan and, really, his move doesn't affect that at all. This is still all about telling the story from the comic, and I talk to Kirkman all the time. There's always been a long-term plan in place; I don't know about always, but I've had one for a long time. I will say that that long-term plan has always had crazy iterations, like a garden of forking paths. There might be a lot of different ways to the very, very endgame. As we get into the teens [in terms of season number], there's a lot of real-world stuff to consider as well. All sorts of things change, but those changes to the long-term plan and to the comic have always, in my mind, have been things we've had to change because characters have been gone [like Andrea] or are still around [like Carol]. I've always thought that we've been able to get great story out of that. And sometimes, even tell those moments from the comic that I love so much in different ways to surprise people who are so familiar with the book. But as far as the long-term plan, it's a series of long-term plans, and we'll see which one we wind up going with.

Andrew Lincoln and Norman Reedus signed two-year deals that end with season eight. You're also working on a deal with AMC as well. How much of the renewal delay is because of contract talks? Lincoln told us that he "hopes" to be back for season nine.

I wouldn't speak to any of that, but I'm very confident of a tenth season. I think it is a question but there is some business to handle with the things you just said. I'm not sure if they're entirely on the money, as far as timing and everything like that, but I think we are tending to a lot of stuff before we jump into that. In the same respect, there's a super long-term plan and we're continuing to follow it. I know that's a lot of double-talk, but I would say everything is quite cool.

You're confident of at least 10 seasons?

I'm confident of beyond a tenth season — we're building toward the future.

How has Kirkman's Amazon deal changed his role on the show?

Nothing has changed at all. I'd liken it to Skybound [his Image Comics imprint and production company]. Robert has always done a ton of other stuff other than The Walking Dead. He's always been involved, and him doing other stuff doesn't really change that.

Let's talk about Carl. He's bitten on the ribs and living on borrowed time. Walk us through the decision to make such a drastic change from the source material.

I can't get into it too much because it really has to do with the story. That kind of says it all. It's all having to do with the greater story of the season. It will be very apparent, the relationship of this awful incident — this very intense story turn — to the greater story. I don't even need to answer because I know as you're watching it into the next half of the season that you'll get it. It has everything to do with what happens throughout the rest of season eight.

Chandler told THR that this was not his decision to leave the series, since he had just bought a house near the show's Georgia set and is delaying college to focus on acting. Why kill off the character that has, on the series and in the comic, always been seen as representing the future?

This was a story turn, that's it. We did not receive a request [from any actor] or anything like that. This has everything to do with story. It's unbelievably difficult to lose someone you've worked with for as long as we've worked with him. It's been a really tough thing. We're hoping to be telling a story that's worthy of it.

When we talked for the second half of season seven in February, you were optimistic that Chandler's then-desire to attend college would actually make his involvement with the show easier. Did Chandler's desire to go to college, be it sooner or more in the future, play any role in your decision to write him out?

It has nothing to do with real life in any way. All the real-life things were of no concern. In fact, that's the only thing that made it difficult — a real-life relationship with Chandler, how much we love to work with him and how talented he is. The story went in that direction. If people watch the whole season, they will see how incredibly critical it is to the telling of the story.

With such a major departure from the comics — nobody could ever have predicted Carl would be killed off — what kind of discussion did you have with Kirkman about it?

It came down to us talking about the future and how versions of those stories can be told. We want to keep telling the stories form the books and we've had to, again and again, tell stories from the books with characters who are no longer on the show. We did map out the avenues that we're going to go down to tell those stories. That part doesn't change. The lineup, some of the dramatic takeaways, some of the turns of the story, maybe that changes, but it's all to get to the emotional places — the drama, the heartbreak, the triumph — that we see over the course of all those issues of The Walking Dead.

Was it your decision to do this or was it something that Kirkman came to you with?

This came from myself and the writers and tackling this current story that we're telling now and some things for the future. It will be very evident — the relationship of this tragic moment — with the entirety of this story and ultimately the conclusion and resolution of this entire arc.

Carl continues to be a driving force and heir apparent in the comics. How does his death fundamentally change the fabric of the show?

I can't really say what the giant impact is or how this changes the show because it does so in a huge way and it has everything to do with how the next half of the season plays out. It's devastating for the characters and especially how we come to realize how it happened. It happened in a moment that was onscreen. We didn't see the absolute bite, but we saw when it happened and we even saw Carl's reaction to it after it happened in one of the episodes that we've seen this season.

In terms of timelines, is it now clear that the teary/red-eyed Rick in the season premiere was his response to Carl's death?

That part will come into focus. Everything about those shifts in episode 801 in the timeline or in the vision or whatever will absolutely be answered soon. And it has a great deal to do with everything you just saw in 808. It's all very tightly related. You won't have to wait long at all to see how it all fits together.

So might the "flash-forward" from the premiere — which features Carl, alive — be a vision of a future that Rick may see on his own deathbed?

It all fits together with this first half of the season.

Carl's death is among the biggest and most shocking card you could have played outside of killing Rick. Have there been discussions about how much longer Rick is part of the story?

For what you've seen, no character is safe. That wasn't the point of it. There's a really critical part of the story that this serves. The way the story goes and has gone in the comic and on the show over the years, no one is safe. It's just the story will always be the thing that is primary. Any character can fall. Any character could disappear or be gone. That's part of the tragic landscape that these characters traverse. It's one of the things from the very beginning that the characters had to learn how to deal with. It's not a skill you just keep, "Oh, I understand people die, I can keep rolling with that." It's not as simple as that. Then something like this happens. Although they've been through this before, they know they won't be immune to this in the future. The impact upon them is seismic. I wouldn't say it was purely designed to do that to the audience; it wasn't. It turns the story in a critical way toward certain things in the book, actually, to potentially heighten some things that Robert explored years and years ago.

Alexandria is effectively destroyed. Between that and Carl's imminent death, how big of a reset is the second half of the season? This feels less like a remix of the comics — which has always been your approach — and more like a reset.

The destruction of Alexandria comes right out of the book. It was something that hit me pretty hard and made me ask a lot of questions. I wouldn't call the next half of the season a reset; it's very much — in talking to everyone at AMC — a last stand. This is it. This is where the story has been leading, to a conclusion and a resolution.

Will the season end with both Jeffrey Dean Morgan (who plays Negan) and Lincoln returning for season nine in some capacity?

I wouldn't tell you if Jon Snow was coming back if I knew it!

But there is a conclusion to this current "All-Out War" arc this season?

There absolutely is a conclusion. There are these big, sprawling arcs in the book and they end and then Robert shifts into another story entirely. We're going to keep doing that. There's a lot of remixing on the way and a lot of overlap of stories, and some of the borders are not as sharp or defined and some of them are black and white. But yes, we are moving to the last stand.

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