The 33-year-old actor said he enjoyed his new style and found it liberating.
"When I didn't have the wig on, I instantly felt like I could move and speak and react differently. Once we aesthetically stripped a lot of that away, it allowed the whole thing to take on a different attitude," he told Entertainment Weekly.
"It felt like a completely different character, and that was hugely liberating and freeing as an actor because I had become a bit bored with myself."
Cate Blachett, Tom Hiddleston, Tessa Thompson, Idris Elba, Karl Urban, Mark Ruffalo, Jeff Goldblum and Anthony Hopkins will also feature in the film.