Adam Driver Joins Marvel’s X-Men Reboot as “Nathaniel Milbury” — And Comic Fans Already Know Who That Really Is

Marvel Studios closed out its D23 2026 presentation with a surprise that took even seasoned fans a moment to fully register. Actor Adam Driver appeared on screen to reveal his role in the studio’s long-awaited X-Men reboot, and rather than announcing a familiar hero or villain name, he introduced a character called Nathaniel Milbury. For casual viewers in the arena, the name meant little. For longtime readers of X-Men comics, it meant a great deal.

What Happened at D23

Marvel Studios president Kevin Feige used the final moments of the studio’s Friday night showcase at Disney’s D23 event in Anaheim, California, to unveil the principal cast of its rebooted X-Men film. According to Marvel’s own recap of the event, director Jake Schreier appeared on stage alongside stars Sadie Sink, Kit Connor, Christopher Abbott, Samara Weaving, Inde Navarrette, and Maya Boyd, who play Jean Grey, Cyclops, Professor Charles Xavier, Emma Frost, Rogue, and Storm respectively.

The final reveal was saved for last, and it did not happen in person. Adam Driver appeared through a pre-recorded video message, explaining that he was joining the film from a soundstage overseas rather than from the event itself. He began by suggesting he would be playing Magneto, then corrected himself mid-sentence and named his actual role as Nathaniel Milbury.

The moment drew a big reaction from the crowd, though for a different reason than Marvel may have anticipated. Several outlets covering the event, including Marvel’s official announcement, noted that Driver joked about playing Magneto before pivoting to his real role, which he framed as an even better part to land.

Who Is Nathaniel Milbury in the Comics

Marvel did not use the words “Mister Sinister” during the announcement, but it did not need to. According to reporting from Primetimer, the Milbury name is an alias long used in the comics by Nathaniel Essex, the character better known as Mister Sinister, one of the X-Men’s oldest and most enduring villains.

In the source material, Essex began as a Victorian-era scientist fascinated by human evolution. Coverage from Tech Times describes him as a geneticist whose fixation on genetic “perfection” eventually made him one of the most direct embodiments of eugenic ideology in the Marvel Universe. Over the course of the comics, Essex is transformed into a near-immortal being by the ancient mutant Apocalypse, after which he spends centuries manipulating mutant bloodlines and experimenting on his test subjects.

The specific choice of the Milbury alias is not random. Primetimer’s report explains that the name ties to a storyline in which Sinister secretly ran a Nebraska orphanage and experimented on a young Scott Summers, the boy who eventually becomes Cyclops, one of the X-Men’s founding members. That detail is notable given that Kit Connor has been cast as Cyclops in the same film, which has fueled speculation among fans about how the two characters might intersect on screen.

Why Fans Reacted So Quickly

Within hours of the announcement, comic fans and entertainment outlets had connected the dots publicly. A report from 3DVF noted that the announcement quietly put an end to months of rumors that Driver had been cast as Magneto, a rumor Driver himself appeared to reference and then dismiss during his video appearance.

Marvel has not officially confirmed that Driver is playing Mister Sinister. As Primetimer and other outlets have pointed out, the studio’s statements so far only use the Nathaniel Milbury name. Still, the alias is specific enough, and the character’s comic book history well known enough, that most coverage of the announcement has treated the connection as effectively confirmed in all but name.

The Rest of the Cast and Release Details

The X-Men reboot now has seven confirmed principal cast members. Sadie Sink stars as Jean Grey, a role she first stepped into briefly in Spider-Man: Brand New Day. Kit Connor plays Scott Summers, known to fans as Cyclops. Christopher Abbott takes on Professor Charles Xavier, while Samara Weaving plays Emma Frost. Inde Navarrette and Maya Boyd round out the announced cast as Rogue and Storm.

Jake Schreier, who directed Marvel Studios’ Thunderbolts*, is directing the new X-Men film. Multiple outlets, including Deadline and The Hollywood Reporter, confirm that the movie is scheduled for a theatrical release on May 5, 2028. Feige indicated during the panel that additional casting news for the film is still to come.

What This Means for the Film

If Driver’s character is indeed Mister Sinister, it would give the rebooted X-Men franchise one of its most formidable comic book villains right out of the gate, and one whose story ties directly into the origins of multiple heroes already cast in the film. Sinister’s connection to Cyclops, and by extension to the wider Summers family in the comics, suggests the character could play a significant role in shaping the new franchise’s mythology rather than serving as a one-film antagonist.

For now, Marvel is letting the Nathaniel Milbury name do the talking. Whether the studio confirms the Mister Sinister connection outright, or continues to let fans piece it together themselves, is likely to remain part of the film’s marketing strategy as more details emerge ahead of its 2028 release.

FAQs

Who is playing Nathaniel Milbury in the new X-Men movie?

Adam Driver was announced as Nathaniel Milbury during Marvel Studios’ D23 2026 panel.

Is Nathaniel Milbury the same as Mister Sinister?

Marvel has not officially confirmed this, but Nathaniel Milbury is a well-known alias used by Nathaniel Essex, the comic book character known as Mister Sinister. Most entertainment outlets covering the announcement have treated the connection as effectively confirmed based on the name alone.

When does the new X-Men movie come out?

The untitled X-Men reboot is scheduled for a theatrical release on May 5, 2028.

Who else is in the X-Men reboot cast?

The announced cast includes Sadie Sink as Jean Grey, Kit Connor as Cyclops, Christopher Abbott as Professor X, Samara Weaving as Emma Frost, Inde Navarrette as Rogue, and Maya Boyd as Storm, alongside Adam Driver.

Who is directing the X-Men reboot?

Jake Schreier, who previously directed Marvel Studios’ Thunderbolts*, is directing the film.

Was Adam Driver rumored to play Magneto before this announcement?

Yes. Several reports noted that Driver had long been rumored for other prominent Marvel roles, including Magneto, and he referenced this rumor himself during his video announcement before revealing his actual role.