The already enormous Avengers: Doomsday ensemble is still holding back some surprises.

Directors Joe and Anthony Russo have confirmed that additional characters and actors will appear in the team-up superhero movie beyond the 31 Marvel characters announced so far. Their comments also leave open the possibility that Mark Ruffalo’s Hulk could be among the film’s still-secret additions.

Addressing Bruce Banner’s place in the story, Joe Russo said, “He is certainly involved in the story that revolves around Doom. We will not confirm nor deny his appearance in Doomsday.”

That stops short of confirming Ruffalo’s return, but it establishes that Banner is connected to the narrative surrounding Robert Downey Jr.’s Victor von Doom.

Anthony Russo was more direct about the existence of unannounced cast members. “The farthest we can go is to say, there are characters and actors who have not been announced, who are a part of Doomsday,” he said.

A 31-character roster — with more to come

The confirmed lineup already spans several groups of Marvel characters. Among the returning MCU veterans are Chris Evans as Steve Rogers/Captain America, Chris Hemsworth as Thor, Anthony Mackie as Sam Wilson/Captain America and Sebastian Stan as Bucky Barnes/Winter Soldier.

Paul Rudd will appear as Ant-Man/Scott Lang, while Tom Hiddleston returns as Loki. The roster also includes Simu Liu as Shang-Chi, Letitia Wright as Shuri/Black Panther, Winston Duke as M’Baku, Tenoch Huerta Mejía as Namor and Danny Ramirez as Falcon/Joaquin Torres.

The Fantastic Four contingent consists of Pedro Pascal as Reed Richards/Mister Fantastic, Vanessa Kirby as Sue Storm/Invisible Woman, Joseph Quinn as Johnny Storm/Human Torch and Ebon Moss-Bachrach as Ben Grimm/The Thing.

Five members of the Thunderbolts/New Avengers lineup have also been confirmed: Florence Pugh as Yelena Belova, David Harbour as Red Guardian/Alexei Shostakov, Wyatt Russell as U.S. Agent/John Walker, Hannah John-Kamen as Ghost/Ava Starr and Lewis Pullman as Sentry/Bob Reynolds.

The film will additionally feature a group of X-Men and Fox-era characters. Patrick Stewart is playing Professor Charles Xavier, with Ian McKellen as Magneto/Erik Lehnsherr, James Marsden as Cyclops/Scott Summers and Kelsey Grammer as Beast/Hank McCoy.

Alan Cumming will appear as Nightcrawler/Kurt Wagner, Rebecca Romijn as Mystique/Raven and Channing Tatum as Gambit/Remy LeBeau.

Rounding out the announced cast are Downey as Doctor Doom/Victor von Doom, Kathryn Newton as Cassie Lang, Hayley Atwell as Peggy Carter and Mabel Cadena as Namora.

The script remained in motion during production

While discussing the scale of the project, Anthony Russo described the MCU as “this massive experiment in how vast, how much scope can an ensemble really have?”

The directors also confirmed that filming on Doomsday began before the screenplay was completed. Joe Russo explained that their process allows the material to continue developing as performers join the production.

“We always view the script as a living organism,” he said. “We’re improvisation-based, rehearsal-based directors. We like to see what the actors bring to the characters, and sometimes you don’t get the actors until a few days or a few weeks before you shoot them. And a lot of the time, that’s when the magic happens.”

How Endgame leads into Doomsday

Joe and Anthony Russo are also promoting the theatrical re-release of Avengers: Endgame, which earned another $86 million over the weekend. The film originally grossed $2.8 billion in 2019.

The re-released version now contains four new end-credits scenes designed to help set up Avengers: Doomsday. Joe Russo has previously described Endgame as “required viewing for following the story in Doomsday.”

What Happens Next?

Avengers: Doomsday opens in theaters Dec. 18. With the Russos confirming that the public cast list remains incomplete, more characters and actors are still waiting to be revealed. Hulk’s appearance, however, remains deliberately unconfirmed.