Sam Rockwell as Justin Hammer in Iron Man 2

This is the fictional character biography of Justin Hammer:

He is a multi-billionaire businessman. He was born in Surrey, England, and later became a citizen of Monaco.  An industrialist, a rival of industrialist Tony Stark, later became a criminal financier using unethical methods.  In exchange for fifty percent of the crime profits, he would pay bail for costumed criminals and finance the development and replacement of both their weaponry and equipment...

...and based on the this image,

He is much older than Stark!!! 
So, what happened?





Rockwell told MTV News:

    “They wanted to go with a rival for Tony Stark who is closer to his age, and make him American”













Now, accoding to MTV Splash Page 'EXCLUSIVE'
posted by Rick Marshall

Movie Trailers - Movies Blog

When "Iron Man 2" actor Sam Rockwell dropped by Splash Page HQ recently, we asked him about the relationship between his character (rival industrialist Justin Hammer) and Don Cheadle's character (Stark's military buddy James "Rhodey" Rhodes). After all, they seemed pretty chummy in the "Iron Man 2" trailer that premiered during Comic-Con in San Diego this year.

"Don and I, we're working together," said Rockwell of the pair's relationship. "He works with me in spite of some of my personality flaws."

Pressed for more details about those "personality flaws," Rockwell called Hammer "a bit of a shark." According to the actor, Hammer's relationship with Rhodes is one of necessity, not of choice.

"Don's character, Rhodey, needs to work with me. He has no choice," said Rockwell. "So we team up and we build this fabulous War Machine."

Knowing that his character played an integral role in creating the War Machine armor, one would think he'd take advantage of the opportunity to try it on. Unfortunately, it wasn't meant to be.

"I really wanted to, but Don wouldn't let me," said Rockwell.


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