Rebecca Hall ("The Town") is in talks to join Marvel Studios and Disney's "Iron Man 3," that starts production this month.
Thesp would play a scientist who plays a pivotal role in the creation of a nanotechnology, known as Extremis, that winds up being sold to terrorists.
Jessica Chastain announced on her Facebook page, on Monday, she would not be playing the part, due to conflicting projects, after press reports prematurely attached her to the pic.
Shane Black is helming and co-writing "Iron Man 3," with Drew Pearce, that brings back Robert Downey Jr. as billionaire Tony Stark and his superhero alter ego Iron Man, along with Gwyneth Paltrow and Don Cheadle. Guy Pearce also is on board, while Ben Kingsley is set to play the villain.
Plot will borrow elements from Warren Ellis' six-issue "Iron Man: Extremis," that also heavily influenced the first "Iron Man" pic, and focuses on the spread of a virus through nanotechnology.
Production on the film starts this month in North Carolina before moving to China. Disney already has skedded to release "Iron Man 3" on May 3, 2013.