AMC’s The Walking Dead may have just stunned fans of the diehard zombie drama and comic series that it is based on.

During Sunday’s episode — the third of season six — fan favorite Glenn (Steven Yeun) appeared to be shockingly killed off when Nicholas (Michael Traynor) killed himself as they were surrounded by zombies with no hope for escape or rescue.

While Glenn’s death doesn’t come until much later in the comic series on which the AMC drama is based and the episode didn’t seem 100 percent definitive, showrunner Scott M. Gimple offered the following statement on Glenn’s fate during Sunday’s Talking Dead — where the character, one of five remaining originals from season one, was not included in its “In Memoriam” segment:

“Dear fans of The Walking Dead, this is a hard story to tell and when we were planning to tell we knew our friends at the Talking Dead would be talking to you about it and knowing you’d all be talking, and feeling and commiserating, I knew we should say something about it lest our silence say something we didn’t mean to say or not say,” Gimple said in a statement. “So I’ll say this: In some way, we will see Glenn, some version of Glenn or parts of Glenn again, either in flashback or in the current story to help complete the story.”

A big spoiler alert for those who haven’t read creator/exec producer Kirkman’s comics: Glenn is shockingly executed during the group’s first confrontation with dastardly villain Negan in its landmark 100th issue. Sources tell THR that the character of Negan will be introduced in the season six finale, with casting currently under way for the role (under the fake name of Orin). Sources also say that fan-favorite Yeun recently signed a new deal to remain on the zombie drama, further indicating that his death at such an early point in the AMC story seems unlikely.

One of The Walking Dead‘s original five stars shockingly appearedto be killed off during Sunday’s deadly episode.

The third episode of season six, titled “Thank You,” closed with Steven Yeun’s Glenn — now the group’s moral compass — seemingly having his intestines ripped apart by the undead.

Throughout the hour, Nicholas (Michael Traynor) — the same guy responsible for the death of Noah (Tyler James Williams) during season five — had experienced mental breakdowns, causing him to check out as he and Glenn scrambled to find a building to set on fire in an effort to lead the thousands of walkers away from Alexandria.

Despite the fact that he was a supply runner — the same role Glenn had served — Nicholas, like his fellow Alexandrians, is unaccustomed to facing serious threats and ill-prepared to survive in the new world.

After Nicholas had to put down a 19-year-old former member of his supply running group who turned and was trapped under an abandoned car, he was tasked with leading Glenn to a feed store he recommended to set ablaze. Upon learning the location had already been burned down, a checked out Nicholas led Glenn down an alley that ultimately had no way out after the zombie herd not only caught up with them but also had them surrounded.

Trapped on top of a dumpster, Nicholas — who completely spaces out to the point of apparent shock — mutters “thank you” to Glenn, points a gun at his head and blows it off. The result sprays Glenn with blood and sends both of them tumbling to the ground and a likely certain death amid the throng of walkers.

The scene is filmed tight on Glenn’s panicked face as walkers seem to be feeding on someone‘s intestines. What the camera never shows is if it’s Nicholas or Glenn’s body that the walkers are devouring as the camera pans out to show what viewers are left to imagine are both of their bodies buried under the sea of blood-thirsty roamers.

But is Glenn really dead?

The concept of using a body — or covering a human with zombie blood — has been used several times on both the AMC series and in Robert Kirkman’s comics on which the drama is based. The idea that the walkers are consuming Nicholas’ dead body while Glenn hides underneath it is entirely possible. That would give the episode title — “Thank You” — a dual meaning as it could represent both the words Nicholas said as a way to repay Glenn for giving him a second chance after Noah’s death, as well as Glenn morbidly thanking Nicholas for shielding him from certain death.

Another distinct possibility is that the cowardly Nicholas was hallucinating the entire sequence of events at the moment when the duo stood atop the dumpster as he mentally zones out, meaning neither of them are on death’s door. (Although it’s worth noting that Glenn also reassured Nicholas that he was “not that person” anymore during Sunday’s episode.)

Also not out of the question is the idea that The Walking Dead is playing around with its timeline — as it did during the 90-minute season six premiere, which jumped from the past and present — and this is some sort of nightmare that a very much alive Nicholas (or Glenn) are having in the future.

Further proving the theory that Glenn isn’t really dead is the fact that Yeun has been spotted on set multiple times during production on the second half of the season. However, it’s unclear whether Yeun’s continued work comes via flashbacks or visions, like former star Sarah Wayne Callies, whose Lori returned years after her character was killed off.

A big spoiler alert for those who haven’t read creator/exec producer Kirkman’s comics: Glenn is shockingly executed during the group’s first confrontation with dastardly villain Negan in its landmark 100th issue. Sources tell THR that the character of Negan will be introduced in the season six finale, with casting currently under way for the role (under the fake name of Orin). Sources also say that fan-favorite Yeun recently signed a new deal to remain on the zombie drama, further indicating that his death at such an early point in the AMC story seems unlikely.

Were the AMC series to really kill Glenn off in such an unceremonious fashion — alone and dead effectively at the hands of Nicholas, who ignored his guide to the new world and sacrificed Noah to save himself — it would be a major departure from what is hailed as one of the comic series’ most defining issues.

Should Glenn, in fact, be killed off during the episode, it would also mark the second major departure from the source material. Andrea (played by Laurie Holden) was surprisingly killed off during the season three finale. The Andrea in the comics — now on issue 147 — is still alive and is Rick’s love interest and a leader at Alexandria. Plus, killing off a beloved character such as Glenn would typically happen during a major episode, like the midseason or season finale, as happened with Andrea.

As if Glenn’s potential death wasn’t enough, Sunday’s episode also left series lead Rick (Andrew Lincoln) in peril with a bloodied hand in a stalled RV, surrounded by the zombie herd after executing five members of the Wolves. The hour also featured the brutal deaths of at least four other Alexandrians, who were traveling with Rick’s crew on a mission to detour the zombie herd away from their gated community.

Given the evidence, do you think Glenn is dead?