Chastain in talks for Iron Man 3

Jessica Chastain is apparently back in negotiations to join Iron Man 3.

The Oscar-nominated actress could be starring opposite Robert Downey Jr in the third instalment of the Marvel superhero series, reported Deadline.

The star of The Tree Of Life, Take Shelter and The Help is tipped to portray a "sexy scientist", who is "every bit as smart as Tony Stark" in Shane Black's upcoming action adventure.

Robert is set to reprise his superhero alter-ego, alongside Gwyneth Paltrow as his eager assistant Pepper Potts.

Don Cheadle, Sir Ben Kingsley and Guy Pearce could also be joining Iron Man 3.

Producer Kevin Feige revealed that work on the third film is due to begin shortly.

"Robert and I go to North Carolina after this - in five weeks' time - and we start filming Iron Man 3. There will be some scenes in China, because we are doing a co-production with them," he said.