It's safe to say that Benedict Cumberbatch is a big, big fan of his "Hobbit: The Battle of the Five Armies" co-star Andy Serkis.

"I learned a great deal by watching Andy's work, not least when Pete [Jackson] showed me a little unfinished clip of the riddle scene in an 'An Unexpected Journey.' And it was him as Gollum completely, and then it all faded away and it was him in the suit, and then after about three seconds you forgot that it was Andy acting in a suit, you just saw nothing but Gollum...it is the most phenomenally realized performance in the flesh," said the "Sherlock" star of how Serkis helped influence his motion-capture performance as Smaug the dragon in the "Hobbit" films. "Everything that you see...is all in the performance. It all comes from that."

So now that the final installment in the Middle-earth franchise that launched his career is wrapping up, how does Serkis sum up the technology's influence on cinema?

"Peter Jackson had an idea which is a key idea which is the really big transformational shift, which is that you don't have two actors in a scene imagining what a third character is doing," said Serkis of the essential difference between green-screen and motion-capture. "And what has happened is that through playing [Gollum], it has opened up...a transformation from visual effects to character."

For more from the "Hobbit" co-stars, including further discussion of the motion-capture process and how the final battle is as much an emotional fight as a physical one, check out the full interview embedded above.

"The Hobbit: The Battle of the Five Armies" hits theaters on December 17.