‘Ironheart’ Finale Unleashes a Sinister Surprise, as a Major Marvel Villain Finally Enters the MCU

Editor’s Note: This article contains major spoilers from Episodes 4 to 6 of Ironheart. Continue reading at your own risk.

Marvel has finally done it. After years of rumors, fan theories, and endless online chatter, Mephisto is officially in the Marvel Cinematic Universe. The big reveal came in the final episode of Ironheart, and yes, it’s Sacha Baron Cohen playing the iconic demon.

No one saw it coming quite like this, not even the show’s star Dominique Thorne. She plays Riri Williams, the genius teen behind the Ironheart armor, and even she didn’t know who Cohen was playing until the moment they filmed the big scene.

In a chat with TheWrap, Thorne shared her surprise when the truth finally came out during production. “That’s when I knew, ‘Oh! OK, great,’” she said with a laugh. “Even the names were fake. I mean, Marvel, hats off to them. They are so committed to the lore and the secrecy that even us within the cast weren’t sure who it was actually going to be.”

Fans thought The Hood, played by Anthony Ramos, got his powers from Dormammu. That made sense. His magical cloak was dangerous and dark, and the whole season hinted that Dormammu was the source. Zelma, played by Regan Aliyah, even said it out loud. But none of that was true.

In the final moments of the show, Riri meets the mysterious figure who gave Parker Robbins his powers. She thinks she’s looking at Dormammu. He laughs at her. Then he tells her who he really is.

He’s Mephisto.

Thorne told Variety she was just as shocked as everyone else. “I learned in the midst of our shooting,” she said. “So, by the time they gave me the correct name in the script, it was like ‘Whoa, the Reddit guy! The guy from all the rumors. He’s in this show? OK, y’all are serious!’”

It had been rumored for a while that Sacha Baron Cohen was involved in Ironheart, but Marvel never confirmed it. The production kept it under wraps by using fake names in the scripts and keeping things quiet on set. Thorne only found out when she came face to face with Cohen and heard the word “Mephisto” spoken in the scene.

That scene takes place in a wrecked pizza shop. It’s empty. Just one person is sitting there, the man behind Parker’s powers. Riri walks in, thinking she’s talking to Dormammu. But he corrects her. It’s Mephisto, finally showing his face in the MCU.

He offers Riri a deal. Her best friend Natalie is gone again. Riri doesn’t have the money or resources to rebuild the tech she needs. Mephisto says he can fix everything—if she’s willing to pay the price. The episode ends with Riri showing the same glowing marks on her body that Parker had, meaning she may have taken the deal.

So, is Riri now working with a demon?

Thorne didn’t say for sure. “I don’t know,” she told TheWrap. “We might need to keep an eye on her, is all I think I can say for now.”

She also opened up about what that choice means for her character. “I mean, yeah, I know what the right thing to do is, but this is my best friend,” she said. “I can’t get my father back. I can’t get my stepfather back, but my best friend? Right now? Especially as a young person going through that particular transition… that’s such a tender time to have lost someone so close to you.”

Ryan Coogler, who helped produce Ironheart through his company Proximity Media, said the reveal felt like a natural part of Riri’s story. He compared it to how Spider-Man started off dealing with small-time villains and ended up in multiverse chaos.

“Just two kids trying to make a way for themselves and watching Riri get so in over her head… eventually encountering a seemingly all-powerful, mystical being,” Coogler said in a conversation with Variety. “I just absolutely love that we’re not meeting [Mephisto] in WandaVision… You’re meeting him through this stressed-out, young Black genius.”

Head writer Chinaka Hodge said the idea to bring in Mephisto wasn’t there at the start. “We all landed on Mephisto together,” she said, “but there was one of us in the room who led us there.”

Marvel producer Zoie Nagelhout explained that they originally thought about Dormammu as the source of Parker’s power. But once they looked deeper into the themes of the show, Mephisto just fit better. “He offered a sort of interesting and heightened way to tie together the characters’ journeys,” she said.

Director Angela Barnes was the one who pitched Sacha Baron Cohen for the role. According to Nagelhout, “She pitched it, and we couldn’t unsee it.” Once Cohen was on board, Marvel did everything to keep it secret. “If he was outside, we wrapped him up in tarps,” she recalled. “He had to walk like two steps at a time.”

Cohen gave different versions of the character during filming. That works perfectly since Mephisto is known in the comics as a shapeshifter. Hodge joked that “maybe Meryl Streep is in the role in the future.”

Right now, no one knows where Riri will show up next. A second season of Ironheart hasn’t been confirmed, and there’s no official word on whether she’ll return in Black Panther 3 either. Coogler laughed when asked. “I don’t know jack shit,” he said. “I’m here for whatever Chinaka’s got coming at us next; whatever Kevin’s got coming at us next.”

But he knows fans are going to have thoughts. “I think the audience is going to take to that ending and I can’t wait to see those characters again,” he said.

Ironheart is now streaming on Disney+.

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