One of the most interesting characters in the "Avengers: Age of Ultron" is Hulk.

Because he has both a good and bad side just like Dr. Jekyll and Mr. Hyde, many people were curious about how he started turning into a beast that's why solo movies were created about this popular Marvel superhero.

We reported a few months ago about the evolution of Hulk - from Lou Ferrigno's green makeup and shredded shorts to Edward Norton's video-game inspired look. This time, we will see a more realistic Hulk as played by Mark Ruffalo.

ILM President Lynwen Brennan told IGN, "Getting that personality is very important to Joss [Whedon], and it's very important that it's driven by Mark's performance. We've developed a new capture system, which we call Muse, which really captures the actor's performance - it allows us to combine different takes as well. We're using it on Warcraft, and we furthered the development on Avengers."

Could this mean that we will also be seeing a solo movie for Hulk in the future? During an interview with Slash Film, "The Avengers: Age of Ultron" director Joss Whedon revealed that there won't be a "Hulk" film. He said, "We think right now it's good to have somebody who could only be in the Avengers. Everybody loves Mark. He's phenomenal. But the fact that there hasn't been a Hulk [movie] since that Hulk, it doesn't suck.

Whedon added, "My job is hard enough, you know. Cap's had a movie, Thor's had a movie. Everyone's gone through big changes, Iron Man had a movie, and so I have to juggle everybody's perception of that while still making a movie that you can see having not seen any except the first Avengers, or not even that."

The director also admitted that Hulk was one of the most difficult characters to adapt in a film. Joss Whedon said, "Banner has a significant role, and the Hulk, we really held back on him for a long while in the first one. And said, there's something terrible coming that you'll love. And what just what makes the Hulk so hard to write is that you're pretending he's a werewolf when he's a superhero."

He added, "So the question is, how has he progressed? How can we bring changes on what the Hulk does? And that's not just in the screenplay. That's moment to moment, because even when they are putting in post mix and temp mix you know, they have a library of two roars. "Aaarrgh! Uuurrgh!" What if he wasn't roaring? I'm angry, and I'm not roaring. I'm being very polite to a lot of reporters, but I'm filled with rage."

Catch Hulk and the rest of team in "The Avengers: Age of Ultron" on May 1, 2015.