POTENTIAL MAJOR SPOILERS AHEAD
It has been expected that "The Avengers" films will ultimately involve a revolving roster of superhero characters. As actors finish up their multi-contract deals, their characters will depart and be replaced with new ones introduced at different points be it in their own standalone films or in small roles in others.
A new report from Bad Ass Digest though indicates that may be happening a lot quicker than expected. The site seems to have seen an earlier version of the film's script and says that by the end of "Avengers: Age of Ultron," the team roster will be significantly changed.
In fact, 'Ultron' apparently ends with Captain America assembling a whole new team, some familiar faces and some whole new ones, which partly explains all the vague talk about which Marvel heroes will be joining Steve Rogers in the third "Captain America" film.
According to the report, the only new person that appears to be a lock is Ms. Marvel, aka Captain Marvel, but the company is said to be having second thoughts about wedging in the character in what is effectively a cameo and may instead give her a bigger debut in a juicier role somewhere else first - like a film of her own.
In any case it appears the decision doesn't have to be made yet as the make-up of the new team won't be fully determined until the scene is shot. Said scene could be saved for either scheduled reshoots or snuck into the shooting schedule of Captain America 3 in the second quarter of next year.