During a recent interview for his NBC series The Blacklist, the actor revealed he recently spoke with director Joss Whedon about the role, and that he went in and had photographs taken for head and body scans.
"I have spoken to Joss Whedon about it. And yes, actually, just this weekend I went in for them to take very extensive photographs, head scans, body scans, and all kinds of things in preparation for figuring out how the hell I'm gonna fit in this Ultron character!"
Although it hasn't been confirmed, it is possible that James Spader may portray Ultron through motion capture technology, rather than simply providing the voice. In a separate interview, he also spoke about why he agreed to take on this coveted role.
"I think it'll be a lot of fun and it's incredibly nostalgic for me. When I was a kid my best friend had trunks of comics and I didn't have any so I used to love going for sleepovers at his house. Also I have three sons and two of them have a great interest in comics so they're excited I'm playing the role."
In related news, Scarlett Johansson, who is returning as the Black Widow, revealed that production is scheduled to begin this January.
"We'll be shooting that in January. I think we're taking it to the streets this time, I think we're going overseas."
We reported in July that Black Widow and Jeremy Renner's Hawkeye will have much bigger roles in the sequel. Robert Downey Jr. (Iron Man), Chris Hemsworth (Thor), Chris Evans (Captain America), Mark Ruffalo (Hulk), Samuel L. Jackson (Nick Fury) and Cobie Smulders (Agent Maria Hill) are reprising their roles from Marvel's The Avengers, with Aaron Taylor-Johnson and Elizabeth Olsen in negotiations to play Quicksilver and Scarlet Witch.