One of many potential futures Justice League members in James Gunn's Superman trailer is Guy Gardner (Nathan Fillion), the first of many Green Lanterns to run around in the DC Universe. The man with the power ring and cut bowl is also expected to appear in the 2026 DCU series Lanterns, which will focus on Gardner's fellow Green Lanterns Hal Jordan (Kyle Chandler) and Jon Stewart (Aaron Pierre). All in all, life is good for Fillion fans who want to see the star of "Firefly" and "The Rookie" as DC's angriest superhero, starting with his role in Superman. Or is it?

Some DC fans suspect that Gardner's DCU incarnation isn't long for this world. Actually, redditor u/LastCryptographer173 suspected that the abrasive Green Lantern would be the centerpiece of Lanterns as the victim of a high-profile murder, writing:

"I'm still convinced that the mystery that Hal and John are going to investigate is Guy's murder."

The biggest clues about Lanterns come from James Gunn himself. During an appearance by Josh Horowitz "Happy Sad Confused" podcast, Gunn had this to say about the series:

"They are land-bound." It's not in space. We don't have a thousand green lanterns or anything. It's a grounded story told through a different lens in a way that really is—it's an HBO series. and it's going to be an HBO series, I'm happy with that and I love the scripts.

The scripts in question come from the likes of Damon Lindelof ("Watchmen," "Lost," "The Leftovers") and Chris Mundy ("Criminal Minds," "Ozark"), and from DC Studios compared The Lanterns to True Detective It certainly seems like the show will feature a huge crime for Jordan and Stewart to solve. Seeing as Guy Gardner is the main Green Lantern in the comics, but the role he might play on the Lanterns is being kept under wraps, it doesn't seem that unreasonable to theorize that he might be connected to said crime. Redditor u/jjeisy thought about this as well, and suggested that Fillion's age means he probably won't remain a major part of the DCU for too long. As such, their theory goes as follows:

"Guy Gardner (Nathan Fillion) is killed by an unknown assailant. if he wants to rock the vessel he cut before the ring is taken away, he flies off and finds Jon Stewart (Aaron Pierre, this assassination draws the attention of Super Cop Green Lantern, Hal Jordan (Kyle Chandler) to train Jon Stewart while is handling the case."

There is precedent for Nathan Fillion's character to die in a project in close proximity to Gunn, as it happens. In The Suicide Squad (2021), the actor plays TDK, a squad member with detachable arms who dies very early in the film. Could Guy Gardner buckle under the weight of this history, thus providing the central mystery of Lanterns? It remains to be seen, but the idea is intriguing.

Even if this fan theory turns out to be true and Gardner doesn't survive the Lantern series, Fillion fans have no reason to be sad. After all, no matter what happens with Guy Gardner in the long run, the actor can already boast of cornering the Green Lantern market somewhat. This is because Fillion already has another Green Lantern role besides Guy Gardner in Superman below his belt. In 2011, he did what Ryan Reynolds couldn't, giving fans a critically acclaimed version of Hal Jordan. Granted, Fillion's Jordan is animated, but his Green Lantern: Emerald Knights still received far better reviews than Reynolds' live-action Green Lantern of the same year. Fillion went on to reprise the voice role in 2012's Justice League: Doom.

Superman opens in theaters on July 11, 2025.