Now, as always, we should consider this a rumour until confirmed by Marvel, although the report is being supported by HitFix, who state that: "In Age Of Ultron, Baron Von Strucker is the initial threat, the guy they're fighting at the start of the film. He does not have a major ongoing role in the film, but he is responsible for bringing Quicksilver and the Scarlet Witch into contact with the Avengers in the first place, since they start the film working either with or or the Baron. If you look at this like a James Bond movie, Von Strucker's the bad guy they'll take care of in the pre-credits sequence before they move into the main story. Quicksilver and the Scarlet Witch have a complicated journey in this film, and the question of whether they're good or bad is one of the big things driving the movie overall."
The Avengers: Age of Ultron is set for release on May 1st 2015, with a cast that includes Robert Downey Jr. (Iron Man), Chris Hemsworth (Thor), Chris Evans (Captain America), Scarlett Johansson (Black Widow), Mark Ruffalo (The Incredible Hulk), Samuel L. Jackson (Nick Fury), Don Cheadle (War Machine), Cobie Smulders (Maria Hill), and James Spader (Ultron).