Is James Gunn’s Man of Tomorrow Replacing Nathan Fillion’s Green Lantern?

Man of Tomorrow will continue Superman’s story in the new DC Universe, bringing back many of the characters who appeared in the hero’s debut, but it seems like Nathan Fillion’s Guy Gardner might be getting replaced. David Corenswet’s Superman played a crucial role in the DCU’s Chapter One, leading the franchise’s first movie, which ended up becoming a worldwide box office hit.

That quickly led to a Superman sequel being greenlit, and Man of Tomorrow‘s story makes the film a two-hander between Corenswet’s Clark Kent and Nicholas Hoult’s Lex Luthor. The duo will team up to take down Lars Eidinger’s Brainiac, a villain so powerful that several heroes are likely to show up to help Superman and Lex stop him. However, there is a notable absence so far.

Man Of Tomorrow Just Added A New Green Lantern Actor

Superman‘s cast of characters featured quite a few DC Universe heroes. Supergirl, Mr. Terrific, Hawkgirl, Metamorpho, Peacemaker, and the Green Lantern Guy Gardner showed up with different roles in the 2025 movie. Nathan Fillion gave life to Guy, who was a member of the Justice Gang. Through that, it seemed like the character was an easy choice for the DCU’s eventual Justice League.

However, the latest Man of Tomorrow casting update has put Guy Gardner’s future in doubt. Two new Green Lanterns will debut in the DCU’s slate of releases in 2026, as Aaron Pierre’s John Stewart and Kyle Chandler’s Hal Jordan investigate a small-town mystery in HBO’s Lanterns. After that, Pierre will reportedly return as Green Lantern in James Gunn’s Man of Tomorrow.

At this time, the extent of his role in the movie has yet to be revealed. Neither Pierre nor Gunn has commented on the reports. That said, it would make sense for John Stewart to make the trip to the big screen. After all, Lanterns‘ first trailer made it clear that the DCU is setting him up as the franchise’s main Green Lantern.

The show does that by having Green Lantern Corps veteran Hal Jordan train John, with the latter noting how the older hero is not the future of the Green Lanterns, saying, “You’re old. You’re tired. And your time is up.” John Stewart has been part of several Justice League rosters in comics, games, and in animation, including Justice League Unlimited. He fits that role well.

John Stewart Could Be Replacing Guy Gardner As the DCU’s Main Green Lantern

While Lanterns is clearly setting up John Stewart as Hal Jordan’s replacement, the hero might also be replacing another human Green Lantern soon. After all, Nathan Fillion’s Guy Gardner was the first live-action Green Lantern of the DCU, with the character being a scene-stealer in Superman. His Justice Gang role seemingly meant that Guy would be a major character in the franchise moving forward.

However, the casting reports that revealed Aaron Pierre’s John Stewart was joining the Superman sequel made no mention of Fillion. Several Superman cast members have been reported to be coming back for the sequel, including Rachel Brosnahan (Lois Lane), Skyler Gisondo (Jimmy Olsen), Sara Sampaio (Eve Teschmacher), Isabela Merced (Hawkgirl), and María Gabriela de Faría. Of course, Corenswet and Hoult are also back.

With Hawkgirl appearing in Man of Tomorrow, and a version of the character being romantically linked to John Stewart in the animated Justice League, something that Isabela Merced has said before in interviews that she would like to explore, Aaron Pierre could have a sizable role in the movie. Would that mean replacing Guy in the Justice Gang? Possibly.

How Lanterns Could Set Up John Stewart Appearing In Man Of Tomorrow

While DC has yet to confirm whether Fillion will return as Guy Gardner in Man of Tomorrow, the studio has already revealed that the character will play a role in HBO’s Lanterns. There, fans should see him interacting with Pierre’s John Stewart, likely connected to what role the latter will play in the Superman movie sequel.

For instance, if Guy were to die in Lanterns — Fillion is 54 while Pierre is 31 — then John could take on his role in the Justice Gang as a way to honor a fallen friend. David Corenswet’s Superman will need all the help he can get to fight Brainiac, and after Guy showed his worth, having a Green Lantern to deal with a cosmic threat is a must.

All this time, fans have been focused on John Stewart being Hal Jordan’s DCU replacement, but having that connection be with Guy Gardner instead would be the kind of curveball that keeps things interesting for the franchise. If John were to stay firmly on Earth as a Justice Gang member, then Kyle Chandler’s Hal Jordan could take on a more cosmic role with the Green Lantern Corps.

Given that Man of Tomorrow will enter production this summer, reportedly before Lanterns debuts on HBO in August, then DC fans could learn what Guy Gardner’s status in the Superman sequel is prior to watching his next on-screen appearance and possible death. That said, it would be interesting to see John be trained by Hal in Lanterns and by Guy in Man of Tomorrow, which is an alternative.