(LOS ANGELES) -- A casting notice has revealed a bit about the plot to the upcoming sequel Avengers: Age of Ultron.
According to the website Feature Film Casting, in the 2015 follow-up, "Loki is gone and the new villain will be the evil robot Ultron, who has the ability to keep upgrading his own strength, making him extremely fearsome. Tony Stark/Iron Man becomes the unwitting creator of Ultron."
The notice also says, "The brother-and-sister team of Quicksilver and the Scarlet Witch become the seventh and eighth members of The Avengers" -- something writer/director Joss Whedon previously explained. "Quicksilver has extreme speed, while Scarlet Witch can cast spells and has telekinesis ability."
Also, as Whedon explained, fans will be seeing more of returning Avengers stars Scarlett Johannson and Jeremy Renner, because, as the note explains of their characters, "Black Widow and Hawkeye will be key figures in the film."
The notice explains that shooting begins in "February, 2014," and that "casting directors are auditioning actors for starring, co-starring, and supporting roles." Stand-ins for the lead actors as well as extras "will be cast closer to the start of filming," according to the memo.
Avengers: Age of Ultron is slated for a May 1, 2015 release.
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