Man of Tomorrow: James Gunn’s Superman Sequel Just Got Its Boldest Update Yet

James Gunn poked the hive again. One brain X-ray on the cover of the Man of Tomorrow script, and DCU fans immediately zeroed in on the obvious: Brainiac. Now the rumor mill says that wasn't just a tease.

The brain scan that launched a thousand Brainiac theories

Gunn posted a shot of the Man of Tomorrow script with an X-ray of someone's skull front and center. That sent Instagram and X into overdrive. He later told EW he knew exactly what kind of chatter that image would spark, but he's not ready to spell out what it means just yet. Translation: he knew what he was doing; he's just not confirming it.

So is Brainiac the villain? The latest

Reputed scooper Daniel Richtman (aka DanielRPK) is now saying Brainiac is locked as the sequel's big bad and the casting is almost done. According to his post on X, DC has already sent an offer out. The ScreenTime account amplified that note on December 14, 2025: Brainiac casting is reportedly nearly done, offer out, via DanielRPK. None of that is official, but the smoke is getting thick.

Who could be Gunn's Brainiac?

Nexus Point News previously reported a short list and said no offer had gone out at that time. Add in another name from a separate insider, and you have a compelling mix of directions this could go. Also in play: NPN heard Gunn wanted someone with a strong build and stature for the role, which points one way more than the others.

• Claes Bang, Matt Smith, Sam Rockwell — per Nexus Point News, those three were among the names in contention on an early shortlist; again, at that stage, no offer had been made
• Dave Bautista — Jeff Sneider has claimed Bautista came up as a frontrunner (via CosmicBookNews), which lines up with the "strong build and stature" note

What Gunn has actually said about the sequel

On The House of R podcast, Gunn said Man of Tomorrow will have a slightly different tone than Superman — less "comic-booky," more grounded in the dynamic between David Corenswet's Clark and Nicholas Hoult's Lex. He wants to dig into Luthor not just as the cackling villain who got nabbed at the end of Superman, but as a person with ridiculous ambition and ego who still, somehow, sees himself as the hero of his own story.

And then there's this line from The Howard Stern Show, which sure sounds like setup for a bigger player entering the chat:

"It's a story about Lex Luthor and Superman having to work together to a certain degree against a much, much bigger threat."

Bigger than Lex after the last film? Brainiac fits that silhouette a little too well.

Quick recap: where Superman left Lex

Superman wrapped with Hoult's Luthor getting caught red-handed. Good triumphed, sure, but that wasn't the last word on Lex. Gunn has said Man of Tomorrow centers both Lex and Clark, which tracks with the whole "unlikely team-up vs. something worse" tease.

The vibe right now

Between that brain teaser on Instagram, DanielRPK's claim that an offer is out, and the running list of names (from wiry and cerebral to physically imposing), it feels like Brainiac's DCU debut is imminent. Also worth noting: Gunn's new DCU era looks pretty healthy so far, so expectations are high for round two.

Release date

Man of Tomorrow hits theaters July 9, 2027.