Last we reported, 2011's "It Girl" Jessica Chastain was the leading contender for the sexy scientist role in 'Iron Man 3,' but then passed. Which opened the door to a new round of casting (and casting rumors). Well, the film has made an offer to another actress, and it's Rebecca Hall, the female lead in 'The Town.'

This comes from Variety, who also note that the film will be shooting this month starting in America, and then moving to China. She would play a scientist involved in nanotechnology that gets sold to terrorists. The plot is based heavily on Warren Ellis's six issue run 'Iron Man: Extremis.'

Hall's definitely a talent, and it's surprising that she hasn't been in bigger Hollywood movies post-'The Town.' She has worked with a number of great directors, and played the lead in Woody Allen's 'Vicky Cristina Barcelona' and was in Christopher Nolan's 'The Prestige.' This would be the highest profile picture of her career, and post-'Avengers,' 'Iron Man 3' is going to get a lot of attention as it will be Marvel's follow up to their billion-dollar success.

And with Shane Black directing and a cast that includes Robert Downey Jr., Don Cheadle, Gwyneth Paltrow, Ben Kingsley and Guy Pearce, the film will be nothing if not interesting.