A Guardians of the Galaxy actor sparked fresh speculation about a possible MCU return after fans noticed a cryptic tease in one of her social media posts potentially tied to Avengers: Doomsday. Guardians of the Galaxy Vol. 3 served as the emotional swan song for the titular team that first hit screens in 2014 under the direction of then-MCU director James Gunn. The 2023 movie gave the Guardians a proper and bittersweet farewell, closing out their main trilogy with high stakes, heartfelt character resolutions, and a clear sense of finality for most of the core group. Chris Pratt's Peter Quill returned to Earth, Drax and Nebula remained on Knowhere to rebuild the community, Gamora stayed with the Ravagers, and Rocket became the new leader of a fresh iteration of the Guardians.
Among those goodbyes was Mantis, played by Pom Klementieff. After joining the team in Guardians of the Galaxy Vol. 2 and appearing in both Avengers: Infinity War and Avengers: Endgame, Mantis exited the MCU at the end of Vol. 3 to explore the galaxy on her own. The character's departure left her future in the MCU deliberately open-ended, but a new social media post has sparked speculation about a return.
In a recent Instagram post, Pom Klementieff shared a photo of a mantis on slide 12 of 18 in a carousel, which alludes to the U.S. release date of Avengers: Doomsday, prompting fans to speculate that she might be teasing a return as Mantis in the MCU's 2026 crossover event.
It's worth noting that Pom Klementieff was not part of the official cast announcement from Marvel Studios. The confirmed ensemble is heavily focused on the returning Avengers, the Fantastic Four from Earth-828, Fox's X-Men actors, and Robert Downey Jr. as Doctor Doom. For some reason, other prominent cosmic heroes, like Captain Marvel and the Guardians of the Galaxy, are notably absent from Doomsday, which is odd given the high-stakes story that deals with the literal end of the Multiverse.
In May 2023, Klementieff already addressed her MCU future after Guardians of the Galaxy Vol. 3, admitting that she's unsure about what will happen with Mantis and the rest of the Guardians, noting, "We have no clue:"
"We don’t know what’s going to happen with the characters, if there’s going to be more movies, if we’re going to come back. We have no clue. Mantis is going to go riding and see what’s up."
Fast forward to March 2026, Pom Klementieff admitted that they "never" talked about a fourth Guardians of the Galaxy movie, pointing out, "it was always imagined as a trilogy:"
"I don’t know. We never talked about a Guardians of the Galaxy Volume 4. It was always imagined as a trilogy."
Based on her remarks, she must have genuinely no clue about what's in the cards for Doomsday. Various reports and rumors have yet to indicate that the Guardians would return in Avengers: Doomsday, but this latest tease could hint at a surprise comeback.
Still, Klementieff has a documented history of drawing inspiration from real mantises for the character. She previously talked about watching videos of them for performance inspiration, meaning that posting a photo of a mantis isn't out of character.
So Will Mantis Return In Avengers: Doomsday?
At this point, it's unclear if Mantis will return alongside the other Guardians of the Galaxy in Avengers: Doomsday, especially since most of the original Guardians received definitive endings in Vol. 3. While this latest tease from Pom Klementieff's Instagram post could simply fuel fan speculation, it remains unconfirmed, with no official word from Marvel on whether she'll rejoin the MCU.
Still, it makes sense for Mantis and the other Guardians to return for a brief stint in Doomsday, considering the "all hands on deck" situation that the MCU heroes of Earth-616 are dealing with the literal end of the world.
It's possible that Sam Wilson's Avengers will find a way to contact the Guardians of the Galaxy as a last resort in the final battle against Robert Downey Jr.'s Doctor Doom. Contacting them makes sense since Rocket's new team remains active and the original members' ending at the end of Vol. 3 left the door open for reunions when the stakes are high enough.
Avengers: Secret Wars could also be an ideal project for Mantis and the other Guardians to return to, since the rumored Battleworld plot offers a clean slate for most characters under Doctor Doom's regime. Whatever the case, seeing the Guardians return is a welcome development for the MCU. Hopefully, they are not too late in helping their fellow heroes of Earth-616.
