In an interview following his cameo on this week's episode of "Marvel's Agents of S.H.I.E.L.D.," Samuel L. Jackson told The Wall Street Journal, "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." Multiple outlets have interpreted that statement as confirmation that, as speculated, Olsen will play Scarlet Witch, but it's worth noting that specific mention of the role was added in brackets, and does not appear to be a part of the original quote.
Olsen, the younger sister of "Full House" alums Mary Kate and Ashley Olsen, received widespread acclaim for her starring role in 2011 indie drama "Martha Marcy May Marlene," and will be seen in Spike Lee's "Oldboy" remake, out this November, and 2014's "Godzilla."
"The Avengers: Age of Ultron" -- the sequel to 2012's "The Avengers," the third highest-grossing film of all time -- is set to add both Scarlet Witch and Quicksilver, the Marvel twins long associated with the Avengers and originally part of the Brotherhood of Evil Mutants in "X-Men," plus "Blacklist" star James Spader as the title villain. "Avengers: Age of Ultron," written and directed by Joss Whedon, is scheduled for release on May 1, 2015.