The British actress, who at one stage was set to play Black Widow in Iron Man 2, has declined the role of Peggy Carter in Joe Johnston's Captain America film. Hero Complex reports that the actress was offered as Marvel's first choice but has officially declined.

The British actress has a Golden Globe winning pedigree and would have added a great deal of acting class to the film but it looks like her desire to commit to other projects has prevented her from taking the Cap role. Whether this is another role filming at the sametime as Cap or it's her considering her future is not known. The Marvel heads like to sign their stars to multiple picture deals which restrains their stars from taking many other projects.

Marvel will now have to go back to their shortlist of other possible female leads to play Peggy Carter which includes fellow Brits Keira Knightley and Alice Eve. I would like to see them extend that list to include a few other actresses, who may not necessarily be British. I think Knightley could do a good job but I wonder how likely she will be to sign on for the film.

The casting of Captain America's support roles will be crucial to its worldwide success. A film about an American super-hero that embodies the ideals of America and American culture may struggle if it can't find the right cast of international actors to support Chris Evans and make it seem more than America saving the world (even though that's what it's all about). It will be interesting to see who Marvel ends up signing.