[WARNING: The following story contains spoilers from Sunday's episode of The Walking Dead. Read at your own risk.]

Fans of The Walking Dead have probably been asking the same question all day: Is he or isn't he?

He, of course, is Glenn Rhee (Steven Yeun), the moral compass of our group of zombie apocalypse survivors. Unfortunately for Glenn, the ever-resilient former pizza delivery boy appeared to meet his end on Sunday's episode. After being trapped atop a dumpster by Nicholas (Michael Traynor) by a pack of walkers, Nicholas decided to shoot himself in the head, sending himself and Glenn both into the arms of the hungry zombies, who appeared to quickly rip open Glenn's torso and begin feasting.

However, many of heartbroken fans instantly began to cling to the hope that everything is not what it appeared and that Glenn will somehow be spared. (The prevailing theory is that Nicholas landed on top of Glenn and it was his insides the walkers were munching on). As for the creative team behind the show, they claim ambiguity was not intended.

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"It certainly looked [like he was dying] from where I was sitting," co-executive producer and zombie special effects guru Greg Nicotero tells TVGuide.com. "I was right there. I was covered in blood in the middle of the pile. I was actually the walker that tore the stomach open."

So is Glenn really dead? Read on to see the rest of Nicotero's take on that much-debated scene and whether he thinks Glenn regrets not killing Nicholas last season.

We saw what we saw last night, but there's already tons of debate that Glenn might not actually be dead. Did the creative team purposefully want to build in some ambiguity?
Greg Nicotero: We choreographed the sequence very specifically in regards to telling the story that we want to tell. Very much like Game of Thrones, where we see Jon Snow [die] and then the next day, everybody's got their opinions... I think we will see Glenn again this season, but in what capacity we don't know. It's great that there's a lot of debate about it, and that just shows the passion of the fans. And six seasons in, this story line just shows that we're really, really committed to not pulling any punches and telling a story that we feel that the audience will respond to. It's not always going to be a happy ending, especially in our world.

In terms of that choreography, you're saying it was meant to be clear that Glenn is dead, right?Nicotero: It certainly looked that way from where I was sitting. I was right there. I was actually covered in blood in the middle of the pile. I was actually the walker that tore the stomach open, so I was in makeup and was sort of conducting the shot from inside the crowd. We choreographed it so when I would tear the stomach open, we had a couple walkers that would reach in and pull intestines this way and pull the stomach that way and get the blood to gurgle up. I think from a Walking Dead standpoint, it was probably the most complicated practical shot that we've done on this show to date because of positioning everybody and keeping the actors safe and having 180 people surging over you. So, it was a very complicated shot to choreograph... and it was very specific choreography in terms of telling the story that we wanted to tell.

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If we assume Glenn is dead, what's the impact on the group? He had basically become the group's moral compass.
Nicotero:
With the death of every character, there's always an absence that's felt, and I think the group dynamic constantly changes. I think what Rick showed in this episode is a little frightening because Rick basically was saying, "They're not all going to make it, and that's okay. Just get back to Alexandria." That's a pretty horrific thought to think that someone will be left behind. ...But I think it's also about the morality of these individual people. When Rick says that to Glenn and Michonne, they don't necessarily agree. Their actions, and especially Glenn's continued attempt to rehabilitate Nicholas -- that's who they are as people. And I think Rick has got a lot to learn from them because Rick's just sort of on a bit of another planet right now.

Glenn did go out of his way to help Nicholas. Is that why Nicholas says, "thank you"?
Nicotero:
Yes. I really take that as Nicholas [realizing he] could have died a coward, but that Glenn chose to help him. ... He's basically grateful for Glenn not killing him at the end of Episode 16 last season and that, even though there are a lot of sequences this season already where Glenn was very hesitant about Nicholas's abilities, he didn't turn his back on him.

Some might argue that Nicholas killing himself in that moment was cowardly.
Nicotero: In that world, I think we've done a very good job of establishing that nobody wants to turn into one of those corpses. So, if you have determined that all else fails, you're going to pull the trigger. You'd rather put yourself out than to spend the rest of eternity walking the earth as an undead.

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Do you think in that moment Glenn had any regrets about letting Nicholas live, since his actions ultimately seem to doom Glenn?
Nicotero:
I don't think Glenn is the kind of character that honestly really ever questioned any of his decisions. He's a smart guy and he gets it. It's who he was in Season 1, when he was a smart-ass kid. I love in the episode when Glenn calls Rick "dumbass" on the walkie talkie because that was a callback to the first episode where he sees him in the tank.

Right, and those kind of callbacks usually are made all the more poignant in an episode where a character dies. It feels like it's the end for him, yet so many refuse to accept it. What is your advice to those viewers?
Nicotero:
I think they should watch it about six more times, and I think they should come to their own conclusions because that's what you want to do in any good show. I think that we told the visual story that we wanted to tell and it's just exciting for people to be invested in it. When I watched the Red Wedding, even though I saw all those people die, I still didn't believe it. I was in denial for months. And I physically saw them get their throats cut or get stabbed. I was so invested in those characters that even when I physically saw with my own eyes that they died, I still tried to figure out a way around it. That, to me, is the commitment of watching a show like this. That, to me, is the most exciting part about being a part of a show like this.

So if this was some sort of fake-out, if we do see Glenn again down the line, do you think it would damage the audience's trust in what they're seeing on-screen?
Nicotero: No. I mean, we've had characters come and go. We saw the Governor disappear in Season 3 and then come back in Season 4. We had Merle appear in Season 2 in a dream sequence. We saw Shane come back in a dream sequence. We saw Lori come back in a vision for Rick. I think we've established these rules that even dead characters move in and out of this universe. So, I don't think it would in any way impact the show negatively because I think we've already established those rules.

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Your work on all the extra zombies has been impressive this season. How much of a challenge was it to bring back the zombie threat in such a huge way?
Nicotero:
It's always a great challenge. This season we knew coming out of the gate that this was going put us to the test. My makeup effects team and I have been committed every single episode to putting things on screen that we haven't done before. Last night's episode, aside from the sheer volume of walkers, there were a ton of gags. We saw Barnes gets his throat torn out. Sturgess is ripped apart, and Annie dies. It wasn't just, "Oh, we're doing a bunch of zombie makeup." That was tremendously challenging and we have never worked harder on this show. And I tremendously appreciate you saying that because that means our work is being noticed. After six years, the attention to detail that myself and my crew continue to dedicate to the show is very important.

The Walking Dead airs Sundays at 9/8c on AMC. Do you think Glenn is still alive?