Bruce Banner (Marvel Cinematic Universe)

Bruce Banner, more commonly known by his alter ego the Hulk, is a fictional character in the Marvel Cinematic Universe (MCU) media franchise originally portrayed by Edward Norton and subsequently by Mark Ruffalo—based on the Marvel Comics character of the same name. Banner is depicted as a genius physicist who, after a failed experiment to replicate a super soldier program using gamma radiation, metamorphosis into a large, muscular humanoid creature with green skin whenever his heart rate goes above 200 beats per minute, he is angered, or when facing mortal danger.

Source: Wikipedia — Bruce Banner (Marvel Cinematic Universe) (CC BY-SA 4.0)