"Avengers" star Samuel L. Jackson told The Wall Street Journal that Olsen would be featured in the cast, saying, "I don't think we begin shooting before March of next year. I know we're shooting in London, that James Spader is Ultron and going to be the bad guy, and that we added Ms. [Elizabeth] Olsen [who will play the Scarlet Witch], but I don't know what she's doing, if she's on the inside or the outside. I haven't seen a script." Olsen, who is currently starring as Juliet in the Classic Stage Company's Romeo and Juliet, has acted in the films "Therese," "Kill Your Darlings," "Liberal Arts," "Silent House" and "Martha Marcy May Marlene."

The sixth installment in the Marvel superhero film series, "The Avengers" grossed $1.51 billion worldwide, and was the first Marvel production to generate $1 billion in ticket sales.

Written and directed by Joss Whedon, "The Avengers" featured an ensemble cast that included Jackson, Robert Downey, Jr., Chris Evans, Mark Ruffalo, Chris Hemsworth, Scarlett Johansson, Jeremy Renner, Tom Hiddleston, Clark Gregg, Cobie Smulders and Stellan Skarsgård.