Edward Norton played Bruce Banner in 2008's The Incredible Hulk — the second installment of the Marvel Cinematic Universe revealed to be a secret sequel to Iron Man. The Incredible Hulk told the origin story of Bruce Banner becoming a supersized rage monster after injecting himself with a serum meant to induce immunity to gamma radiation. The film received a mixed reception from critics and fans and remains a unique stand out among MCU films for focusing on story and dialogue over action sequences.

Norton took the portrayal of Banner very seriously, treating it as a once in a lifetime opportunity. However, this was not the first time he had been offered a chance to play the hero. Before Marvel Studios reclaimed the rights to Banner and started on the MCU, Universal had released the 2003 film Hulk starring Eric Bana — a role that had originally been offered to Edward Norton.

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A devoted Hulk fan, Norton turned down the role because he didn't think the script properly honored the character. Norton stated in a report by Total Film, “When the phone rings and someone says, ‘Hey, would you be interested in the big green guy?' there’s that part of all of us that doesn’t want to look like an idiot… There’s the wince factor or the defensive part of you that recoils at what the bad version of what that would be. And I did that, basically. I said ‘no’ to it a couple of times.”

The Incredible Hulk director Zak Penn later discussed the two films when Norton was announced for the latter. “I couldn’t be happier about Ed Norton,” he said. “I worked on the first Hulk movie and I remember talking about how awesome it would be if we got Ed Norton to play this part. He really was up for it the first time. I think Ed Norton’s one of the best actors working, and even I was pretty shocked that he wanted to do it. It’s one of those rare things where it turned out better than I [expected]. Look, there’s a lot of really good actors who wanted to do it even before I wrote my script. I’m not just saying this, but I cannot think of a better person to play Bruce Banner. In this case, Ed Norton would have been at the top of my list.

“To me, the thing about Bruce is that he’s a physicist, he’s a super-smart guy who has a lot of repressed anger. To me, that is the essential thing you need to know about him. He could be tall or short, but you have to believe that he’s a physicist, you have to believe that life is frustrating for him physically. Ed went to Yale. He’s a really smart guy. He has an intelligence that you can see on-screen, which a lot of people who are great actors don’t project that.”

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The Incredible Hulk

Unfortunately, Norton didn't get to play Banner for long, with creative differences causing him to be indefinitely replaced by Mark RuffaloIn a 2010 state press release, Marvel announced that the change will bring on "an actor who embodies the creativity and collaborative spirit of our talented cast members."

Norton gave his own explanation for the departure in a 2014 interview: "I really, really enjoyed it. And yet I looked at the balance of time in life that one spends not only making those sorts of films, but then especially putting them out and obligations that rightly come with that. And there were just a lot of things that - I wanted more diversity - I sort of chose to continue on my path of having a diversity of experiences. Maybe on some unconscious level, I didn't want to have an association with one thing in any way degrade my effectiveness as an actor in characters."

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