Benedict Cumberbatch Says 'There's Something Unholy' About His 'Hobbit' Roles

The actor talks to MTV News about how there's 'no limitations' working in motion capture.

Can you spot Benedict Cumberbatch in "The Hobbit: The Desolation of Smaug"?

Those cheekbones might be missing in action from his dual roles, but the British actor delivers a pair of stunning voice and motion capture performances as the titular dragon and the menacing Necromancer. With audiences' eyes and ears expected to be particularly in tune during his villains' screen time, Cumberbatch went all out to wholly immerse himself and disappear inside the CGI characters.

"For Smaug, I was on my belly and I was trying to articulate as much as humanly possible the movements of this great powerful serpent — this fire-breathing worm. It was a lot of fun, very hard work, but it fed into how the voice should evolve, and the same with the Necromancer," Cumberbatch told MTV News.

As Smaug, Cumberbatch says he channeled the growls of crocodiles to create a "harsh"-sounding voice that was "big and powerful and present" but also one that "sounded old, that sounded racked with a lot of fire and age." The Necromancer, meanwhile, speaks with a more "whispery and spirit-like" sound.

"I had the bold idea to increase my workload by doing it backwards, which we did and it's in the film," Cumberbatch says of recording the Necromancer's lines. "It sounds — it's horrible. There's something very unholy about it."

While motion-capture pioneer Andy Serkis wasn't on set for Cumberbatch's stint, the actor worked one-on-one with Peter Jackson.

"It was so much fun to do," Cumberbatch says of the "mo-cap" experience. "You have no limitations. You're in a bland room like this, but you can do whatever you want. You're a kid in a bedroom again."

"The Hobbit: The Desolation of Smaug," the second in a three-part series for Warner Bros., hits theaters December 13.