Before Edward Norton landed the lead role in 2008's The Incredible Hulk, Mark Ruffalo had a shot at the role that he'd eventually land years later.

With The Story of Marvel Studios: The Making of the Marvel Cinematic Universe out now, numerous details about the evolution of the MCU have been revealed. Now, the full story of how Ruffalo and Norton danced around the role of Bruce Banner has been shared.

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Executive producer David Maisel said that two-time Academy Award nominee Edward Norton was the dream casting choice for the role, but the actor ended up passing on the part initially. All involved were keen to move on to Ruffalo, an up-and-comer who had auditioned for the part. But Maisel wasn't ready to give up, so he took one more swing at Norton. The actor ended up signing on, leaving Ruffalo to wait until negotiations broke down between Norton and Marvel Studios and he was able to step into the recast role.

"One day Mark was cast, and then over a weekend, he was not. It tore my heart," Incredible Hulk director Louis Leterrier said. "Mark was my friend. He had everything, and that's why he is the Hulk now. He had the smarts, the size, the humor, the intelligence, the fragility. We were still writing the script, as is often the case in Hollywood, so I was like, 'Okay, I cannot have Mark. Who can I have?' And because I couldn't have him, I did not try to recast Mark, you know? Edward is an incredible actor. I knew that we could find a very interesting movie with him, but it really changed the movie. I mean, instantly changed it."

As Leterrier notes, the film shifted tonally from the rest of the burgeoning MCU. The future films would go on to hew closely to Iron Man's tone, leaving The Incredible Hulk as a sort of odd duck out in the massive trilogy, and not just because of the recast.

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For now, however, it's the only solo Hulk film Marvel is likely to make given the complicated rights with Universal Studios. But that hasn't stopped Ruffalo's Banner from having a rich arc across the MCU.

Ruffalo will next appear on She-Hulk, which will also bring back Tim Roth as Emil Blonsky/Abomination.

Source: The Story of Marvel Studios: The Making of the Marvel Cinematic Universe