One of the great unknowns for the filmmakers in making Marvel’s The Avengers was how they were going to handle the character of Bruce Banner when he turns into The Hulk. In previous incarnations—with actors Eric Bana and Edward Norton—Bruce Banner and The Hulk were two separate entities with the latter being a completely CGI character void of any physical connection to the actor.
Joss Whedon explains the approach taken in developing the complex character. “We wanted to create a Hulk that had never been done before,” says the director. “In the comics, Bruce Banner and The Hulk didn’t look the same. On the television show they were different actors, and they’ve always been an actor and a CGI creature in the films. But now with the advancements of motion capture technology, we wanted Mark Ruffalo to play both sides of the character.”
The director continues, “Very early on, we decided to build The Hulk’s face off of Mark’s, not just in terms of what he was going to do movement-wise in playing the character, but also the actual physicality of it, including the bone structure and contours of the eyes and mouth. We really wanted to bridge the gap between the characters so that when he turns into The Hulk, you go, ‘Oh my God, that’s Bruce Banner! Only he is big and green and very angry!’”
Mark Ruffalo reveals one aspect of The Hulk that is different from previous incarnations. “In a lot of the other versions of the character, The Hulk grew in size drastically, but in The Avengers he is always going to be about eight-and-a-half feet tall,” says the actor. “He gets stronger as he gets angrier, but he doesn’t really grow much taller.”
“We wanted to incorporate more of the actor than ever before so that the face and mannerisms of The Hulk come from Mark Ruffalo’s face,” says producer Kevin Feige. “We have never done this before, but it was a tremendous help in making audiences feel Bruce Banner and The Hulk were one and the same. When he turns into The Hulk, all of the goodwill we get from a very likable Bruce Banner goes into him and you get more expression, more character, and more emotion than we have ever gotten out of the character.”
“When I found out there was a whole new arena of technology that would allow an actor to play what has always been a CGI character, I thought it could be something cool to try my hand at,” Mark says. “It’s a game changer for The Hulk because it’s hard to capture real anger in a CGI character. Anger is something that’s deep and primordial. There are so many subtleties and variations to it, so this idea of bringing a darker, more humanistic Hulk was really exciting and compelling.”
The filmmakers brought on Industrial Light & Magic (ILM), which worked with visual effects supervisor Janek Sirrs in creating a new version of the character that would incorporate Bruce Banner into the rage and anger of The Hulk. For Joss Whedon, infusing every layer of Mark Ruffalo’s performance into The Hulk was essential in creating the look and feel of the character.
“There are a million things we can build off of from Mark, but at the end of the day, the CGI Hulk needed to feel like flesh and blood, but at the same time had to express everything more dramatically than a human being is going to,” Joss says. “So there have been times when ILM is building off Mark’s performance and I see it and say, ‘We need to take this further; his mouth needs to be opened wider, his head needs to snap quicker.’ All these things had to be augmented in order for them to read as pure Hulk, but they had to come from the basis of reality.”
For Mark, playing both sides of his character meant spending a lot of time at ILM going through the technical processes involved in creating motion capture. He explains how his background in theater helped him with the technical side of the character. “There are many different steps in creating this version of The Hulk,” Mark explains. “It was interesting to me how relatable it is to theater, which is the oldest form of acting. As a theater actor, you walk onto a black box and there is nothing to live off of, so you really have to rely on your imagination, and you have to put things out there that aren’t there.”
The actor continues, “Theater was my training as an actor, and when they put me in this tiny little pod with thousands of cameras and lights all around and I could only move my head, I was able to use my imagination to put myself in the circumstance of fighting Thor or any other being.”
Another aspect of the process that Mark enjoyed was the first glimpse of what he would look like as The Hulk on the big screen. “We went into a space that was as big as a warehouse with a ton of cameras all around, and ILM put a motion capture suit on me,” Mark says. “There was this four-by-six foot monitor. You step out in front of it and incredibly you see The Hulk looking back at you.
“Every movement you make, you see The Hulk making the same movement in the monitor, so the image starts to tell you how the character stands and behaves,” Mark continues. “You also see that the body can only move certain ways, so you’re creating the character based on the physical presence that’s in front of you, which was really exciting and challenging.” Expounding on this unique experience, the actor says, ”I spent several days there and we went through fights, like Hulk against Thor, and I would simulate the fight with one of ILM’s animators for three hours. They took all the information of our movements, put it into a computer, and that becomes the basis for The Hulk. It’s very complex, methodical, and in a lot of ways, a really nascent technology.”
“It’s a creature but it also feels human, and I’m thrilled by it,” praises Mark Ruffalo. “My experience in a lot of these types of films is that you feel like you’re watching two movies—the CGI movie and the human portion. But now we’re free as actors through this technology, and audiences can stay connected and track the character for the entire film.”