Mark Ruffalo is best known as an indie-type actor who has appeared in romantic comedies like "13 Going on 30" and "Date Night," and most notably the critically acclaimed drama "The Kids Are All Right." So it might strike some as an odd choice for the nice guy to play mild-mannered scientist Bruce Banner, who is capable of such anger it turns him into the Incredible Hulk, an enraged green monster. But maybe that's the point.
The revelations don't stop there -- here are more surprising facts about the actor.
He's an activist:
He turns into a green giant in "The Avengers." And in real life, the actor sees green -- or more likely, blue. His organization, Water Defense, works to stop natural gas drilling (fracking) and looks for cleaner alternatives. The 44-year-old told the May issue of Vogue, "I really consider myself an actor, but right now, I am driven to get this going and get people involved."
Samuel Jackson likes to hug him:
The co-star told the New York Daily News, "He's just everybody's little cuddly bear. Everyone loves hugging on Mark." That adorable portrayal of Bruce Banner on screen made his morphing into a monster that much more extreme. Co-star Scarlett Johansson called the actor's transformation "terrifying."
Ruffalo could relate:
The star admits he has had rage issues and that, as a struggling actor in his 20s, "I was the poster definition of an angry young man with a persecution complex," adding,"There was a time if you came into my apartment, there were pictures and posters hanging in very odd places where they were covering fist-holes through walls."
The Hulk wears a leotard:
The things you do for your art. Ruffalo told the Hollywood Reporter that he had to wear a green leotard and crocodile shoes for the motion capture technology to show him as 4,000 pounds of rage on screen. The first time the actor showed up on set, the crew got the giggles. Still, he said at the movie's premiere that while the motion capture outfit "isn't the most flattering, I was really excited to use that technology to bring the Hulk to life in a way that we haven't seen it."
Six film deal?
The character has had several big-screen attempts, with Eric Bana hulking out in 2003 and Ed Norton becoming the angry green giant in 2008. Director Joss Whedon wanted this version of Hulk to channel the sadness of Bill Bixby's character from the popular 1970s TV series. Maybe this turn's the charm.
The actor said in an interview with the Collider that he had to sign a six-movie deal when he came on to "The Avengers." With the all the super reviews, and the whopping $185 million the movie has already made overseas, we may be seeing a lot more of Mark Ruffalo's Hulk.
Watch an 'Avengers' featurette with Mark Ruffalo and costars: