In light of Black Widow's dynamic with the titular villain of Captain America: The Winter Soldier in the comics, it was assumed that the upcoming Marvel sequel would underline the backstory of Scarlett Johansson's Russian spy as it was lightly touched on The Avengers. However, according Chris Evans, "Black Widow's whole arc [in The Winter Soldier] is coming to terms with her history - that she's been a spy, and spies aren't necessarily trustworthy." It seems an in-depth exploration of Natasha Romanoff's (and also likely Clint Barton's) backstory is being saved for The Avengers: Age of Ultron and possibly a solo Black Widow movie, according to Marvel Studios president of production Kevin Feige.
"We start filming the next Avengers film at the end of March," said Feige in the latest issue of Total Film mag'. "[Black] Widow's part in that is very big. We learn more about her past and learn more about where she came from and how she became in that film. The notion of exploring that even further in her own film would be great, and we have some development work with that."
"We wanted to change the dynamic of the cinematic universe with this film," said Feige of Captain America: The Winter Soldier. "We wanted Cap and really the entire cinematic universe to be very different at the end of Winter Solider than it is at the beginning. Therefore when we meet the Avengers at the top of Age of Ultron, it's a very different landscape than we left them at the end of the film film. Partially that's because we love the rhythm that the comic books have developed - each of the characters appear in their runs, occasionally they get together for a big event or crossover series, they part again, and then they come back together again."
The Avengers: Age of Ultron stars Robert Downey Jr., Chris Evans, Mark Ruffalo, Chris Hemsworth, Scarlett Johansson, Cobie Smulders, Jeremy Renner, Aaron Taylor-Johnson, Elizabeth Olsen, with Paul Bettany, Samuel L. Jackson, and James Spader. The film is set for release on May 1, 2015.