A new VFX documentary on "Avengers: Endgame" includes some surprising reveals from special effects producer Jen Underdahl.

The image above depicts Tony Stark (Robert Downey Jr.) wearing his Quantum Realm suit in Marvel’s record-breaking blockbuster “Avengers: Endgame,” but it turns out that suit isn’t actually real. All of the Quantum Realm suits worn in “Endgame” are VFX creations because the film’s production had to start before the costume design team could finalize what the suits would look like. “Endgame” VFX producer Jen Underdahl reveals as much in a new WIRED documentary about the extensive special effects work that went into the Marvel movie (via ScreenRant). “Endgame” was shot back-to-back with “Infinity War” and the production had a tight schedule in order to meet the film’s April 2019 release date. Waiting for the costume designers to finalize the suits was not an option.

“The time suits are a combination of Ant-Man, Tony Stark, and Guardians tech. That took quite a while for us to land on,” Underdahl said. “By the time we got a final version, we were already in principal photography. We knew we were going to build them anyway, since they had to ‘nano’ on and off with Tony’s tech, and it ended up being that the costume department didn’t have time to develop, fit, and fabricate all the costumes for those hero characters, so we ended up doing them digitally.”

The VFX team also had to digitally create Captain Marvel’s full costume any time the Brie Larson superhero appears in “Endgame.” Larson shot her scenes for “Endgame” because she was starting production on her standalone “Captain Marvel” movie, so the costume designers on that film were still figuring out the specifics of her costume when production on “Endgame” got underway.

“Her suit, every time you see it in the movie, when she’s in her full costume, is digital. Again, the designs for those suits were not ready in time for us to photograph Brie. When you saw her at the beginning, as she’s rescuing Tony Stark, when you see her come back, when she’s talking to Nat in the Avengers compound, with Rocket and Nebula, and then in the final battle when she comes back and kind of saves the day, that’s all the digital suit.”

Creating digital costume is one of the reasons “Avengers: Endgame” contains more VFX shots than most contemporary comic book films. The decision to use CGI costumes speaks to Hollywood’s larger production trends on tentpoles, where release dates are set in advance and any delay in filming could be a nightmare for release. Watch WIRED’s “Endgame” VFX documentary in the video below.

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