Learn more about the behind-the-scenes process of realizing the maniacal Ultron for the big screen in the first of two new featurettes for Marvel's Avengers: Age of Ultron, arriving on 3D Digital and Digital HD September 8 and on Blu-ray, DVD, Digital SD and VOD October 2. Stars Robert Downey Jr., Chris Evans and Mark Ruffalo discuss what it was like working with James Spader, while we get to see behind-the-scenes footage of the actor in his motion-capture suit. We also hear from Andy Serkis, who not only played Ulysses Klaue in the superhero sequel, but he also served as a consultant for the motion-capture work.

The second Avengers: Age of Ultron preview features more behind-the-scenes footage of James Spader as Ultron, but his motion-capture outfit is just a bit different this time. Later on in the film, Ultron evolves and becomes a much bigger machine, so to compensate for the size difference, the actor had a large pole mounted to his outfit, which had red dots that represented his eyes. Elizabeth Olsen (Scarlet Witch) explains that it was irritating because she had to look at those fake eyes a few feet above James Spader's head, when she really wanted to watch his performance. We also hear from producer Kevin Feige and director Joss Whedon, who explain why they wanted to bring in both Scarlet Witch and her brother Quicksilver (Aaron Taylor-Johnson) into this story. If that wasn't enough, we also have a third featurette that showcases Paul Bettany's Vision, with the actor taking us through the extensive makeup process.

Marvel Studios presents Avengers: Age of Ultron, the epic follow-up to the biggest superhero movie of all time. When Tony Stark tries to jumpstart a dormant peacekeeping program, things go awry and Earth's Mightiest Heroes, including Iron Man, Captain America, Thor, The Incredible Hulk, Black Widow and Hawkeye, are put to the ultimate test as the fate of the planet hangs in the balance. As the villainous Ultron emerges, it is up to the Avengers to stop him from enacting his terrible plans, and soon uneasy alliances and unexpected action pave the way for an epic and unique global adventure.

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Marvel's Avengers: Age of Ultron stars Robert Downey Jr., who returns as Iron Man, along with Chris Evans as Captain America, Chris Hemsworth as Thor and Mark Ruffalo as The Hulk. Together with Scarlett Johansson as Black Widow and Jeremy Renner as Hawkeye, and with the additional support of Samuel L. Jackson as Nick Fury and Cobie Smulders as Agent Maria Hill, the team must reassemble to defeat James Spader as Ultron, a terrifying technological villain hell-bent on human extinction. Along the way, they confront two mysterious and powerful newcomers, Wanda Maximoff, played by Elizabeth Olsen, and Pietro Maximoff, played byAaron Taylor-Johnson, and meet an old friend in a new form when Paul Bettany becomes Vision.

Other bonus features included on the Blu-ray are From The Inside Out - Making Of The Avengers: Age of Ultron, The Infinite Six, which will set up Avengers: Infinity War Part 1, Global Adventure, Deleted & Extended Scenes with Audio Commentary By Joss Whedon, a Gag Reel and Audio Commentary With Director Joss Whedon. Marvel is also releasing the 13-disc Marvel Cinematic Universe: Phase Two Collection this December, which will include Iron Man 3, Thor: The Dark World, Captain America: The Winter Soldier, Guardians of the Galaxy, Avengers: Age of Ultron and Ant-Man, along with a "top-secret bonus disc." Check out these new previews for Avengers: Age of Ultron, before picking this up on Digital HD, Blu-ray or DVD.