Ever since the first Iron Man film back in 2008, it's nothing new for a Marvel Studios film to not have a finalized script or for things to radically change while on set.
As such, MCU fans shouldn't really be alarmed by reports that the current script for Avengers: Doomsday isn't finalized yet, despite the fact that the Russos having revealed that filming kicks off today.
But apparently, there's a very special reason why the script isn't finalized, according to recent reports.
It's because Marvel Studios hasn't signed all of the actors yet that it wants to appear in the film.
Per the latest rumors, it seems there are several OG X-Men from the Fox era that haven't signed on yet but are in talks to return, including Halle Berry.
There's also Chris Evans, whose Marvel contract expired with Avengers: Endgame. It probably doesn't help matters that Robert Downey Jr.'s massive Marvel paydays are common knowledge, as the agents for some of the bigger-name stars are likely to try and drive up the price of their client.
In addition to Evans and Berry, also missing from the casting reveal were Mark Ruffalo and Jeremy Renner. Chris Pratt's Star-Lord was also unconfirmed, as was the new team of Guardians being led by Rocket.
Deadpool and Wolverine's Hugh Jackman and Ryan Reynolds were also glaring omissions, along with the three live-action Spider-Men- Tom Holland, Andrew Garfield, and Tobey Maguire.
Kevin Feige recently confirmed that the full cast for Endgame wasn't revealed during the livestream, but perhaps those names weren't left off in an effort to maintain secrecy, perhaps they were left off because Marvel doesn't know if they'll be able to sign their respective actors?
Fight sequences and major plot reveals might be changing daily as more actors board or others make it clear that they're not returning.
The official cast for Avengers: Doomsday, as recently confirmed by Marvel Studios, includes a mix of familiar MCU heroes, returning Fox X-Men characters, and the MCU's new Fantastic Four.
The confirmed characters include Chris Hemsworth as Thor, Vanessa Kirby as Sue Storm / Invisible Woman, Anthony Mackie as Sam Wilson / Captain America, Sebastian Stan as Bucky Barnes / Winter Soldier, Letitia Wright as Shuri / Black Panther, Paul Rudd as Scott Lang / Ant-Man, Wyatt Russell as John Walker / U.S. Agent, Tenoch Huerta Mejía as Namor, Ebon Moss-Bachrach as Ben Grimm / The Thing, and Simu Liu as Shang-Chi.
Also confirmed to appear is Florence Pugh as Yelena Belova / Black Widow, Kelsey Grammer as Hank McCoy / Beast, Lewis Pullman as Bob Reynolds / Sentry, Danny Ramirez as Joaquin Torres / Falcon, Joseph Quinn as Johnny Storm / Human Torch, David Harbour as Alexei Shostakov / Red Guardian, Winston Duke as M'Baku, Hannah John-Kamen as Ava Starr / Ghost, Tom Hiddleston as Loki, Patrick Stewart as Charles Xavier / Professor X, Ian McKellen as Erik Lehnsherr / Magneto, Alan Cumming as Kurt Wagner / Nightcrawler, Rebecca Romijn as Raven Darkhölme / Mystique, James Marsden as Scott Summers / Cyclops, Channing Tatum as Remy LeBeau / Gambit, and Pedro Pascal as Reed Richards / Mister Fantastic.
Iron Man actor Robert Downey Jr. returns to the MCU but not as Tony Stark, he'll be portraying the film's primary villain, Victor von Doom aka Doctor Doom.
The creative team behind Avengers: Doomsday is comprised of a talented group of individuals and familiar faces from the Marvel Cinematic Universe, including the dynamic directing duo Anthony and Joe Russo.
The screenplay for Avengers: Doomsday is penned by Michael Waldron and Stephen McFeely. Waldron is known for his work on Loki and Doctor Strange in the Multiverse of Madness, while McFeely has a long and successful history with Marvel, having co-written Captain America: The First Avenger, Captain America: The Winter Soldier, Captain America: Civil War, Avengers: Infinity War, and Avengers: Endgame.
Avengers: Doomsday is scheduled for release on May 1, 2026. The film is set to be followed by Avengers: Secret Wars on May 7, 2027.