When moviegoers slip on their 3-D glasses this weekend to watch The Hobbit, they’ll see some familiar faces: Gandalf the Grey, Elrond the Elf and, of course, Gollum. The man behind those creepy intonations of “precious” is 48-year-old Andy Serkis. The actor and director is an outspoken proponent of motion capture–the technique animators used to morph him into Gollum—and he can put his résumé where his mouth is: after his work in Peter Jackson’s The Lord of the Rings, he played “mo-cap” leads in King Kong and Rise of the Planet of the Apes. TIME spoke to Serkis about the new Tolkien flick, how he makes Gollum so heart-wrenching and whether motion-capture acting is the same as the “real” thing.
Your big scene in The Hobbit is when Gollum and Bilbo Baggins play a game of riddles in a dark cave. What was the experience like on set?
It was the first thing that was shot on The Hobbit movie, and it’s the seminal Gollum scene in the book. Peter decided to do this scene first because, one, Martin [Freeman] was finding his feet as Bilbo and it was probably easier to do that with one other actor rather than 13 dwarves and a wizard. And the crew could settle back into a world that they knew. Peter was comfortable. And we just had a great deal of fun.
How will the Gollum viewers see in The Hobbit be different from the one in The Lord of the Rings?
Gollum is Gollum—though in Lord of the Rings he’s 600 years old and in The Hobbit he’s 540, so he looks a little bit more handsome. He hasn’t been tortured by Sauron at this point. He also looks incredibly more detailed. The fidelity to [my] facial performance is much greater, and the subtleties in the texturing and the eye movements. So he feels 100% real. Interestingly, at the higher frame rate of 48 frames per second, characters like Gollum work terrifically well.
(READ: Richard Corliss’s review of The Hobbit)
How would you describe the physical side of playing Gollum?
His physicality is borne out of his addiction to the ring. That was always our way into the role. His personality, the involuntary way in which his body spasms when the word Gollum comes out of his mouth, is connected to the guilt that he carries with him in his throat from murdering his cousin. He is described by Tolkien in many different ways, as a puppy with Frodo and a spider and a frog. I based him a lot on Francis Bacon’s paintings, the agony and torture, which are in turn based on Eadweard Muybridge’s photographs. The references for me were very layered.
Your performance on the Lord of the Rings set inspired rewrites that delved deeper into Gollum’s character. How did your role expand in the first trilogy?
When I first went down to New Zealand to work, I was supposed to do just the voice for an animated character. But when I met Peter Jackson, he explained that he wanted the actors playing Sam and Frodo not to act against a tennis ball on a stick but with another actor. Gollum drives most of those scenes, and he wanted the energy and the responses to feel real. When Peter saw what I was doing on set, he filmed my performance with 35 mm. Then, over the course of the three films, we began to employ motion capture.
What was it like playing an enormous gorilla in King Kong?
When I was on set with Naomi Watts, I wore what was in effect a gorilla muscle suit. Then, to get the scale differences, I’d be raised on cranes and on various platforms to get the eye-line right. We nevertheless acted opposite each other. And on set we used a thing called a Kongalizer, which was a pitch modulator that lowered the tone of my voice. And we put some gigantic speakers on set to create his presence, with his breath and in his roars. It was all acted out on set and then repeated entirely on the performance capture stage.
For you, what’s the difference between “motion capture” and “performance capture”?
Motion capture is exactly what it says: it’s physical moves, whereas performance capture is the entire performance—including your facial performance. If you’re doing, say, martial arts for a video game, that is motion capture. This is basically another way of recording an actor’s performance: audio, facial and physical. Somebody called it “emotion capture.” The great thing about working with performance capture is you enter the whole CG world and understand the visual effects side of filmmaking. So that was great education for me.
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There were some unsuccessful Oscar rumblings for your role as Caesar [the supersmart chimpanzee in 2011’s Rise of the Planet of the Apes]? Do you think performance capture characters are getting due credit?
I don’t think there are enough people doing it yet. But I think the perception has shifted. I’ve never, ever made a distinction between playing a live-action character or a performance-capture character. Acting is acting, and it’s really a matter of how that character is clothed and made up. One is before the fact, and one is after the fact.
Do you think the average audience member equates traditional costumes and animation “costumes”?
It’s the character that lives on screen, and it doesn’t really matter if they do or not. But young people and people who watch behind-the-scenes and certainly the video game-playing generation, they totally get it. It’s a high-end version of [Microsoft] Kinect or Wii Sports. They get the connection of commanding an avatar on screen. And that’s exactly what an actor is doing using this technology.
Is there resistance in the industry, like the era of transitioning from silent movies to “talkies”?
Absolutely. That’s always the way. It’s the same with higher frame rates or, as you say, going from silent movies to sound or going from 35mm to digital. It’s inevitable that there will be people who see themselves as purists, who think that prosthetic makeup is the only way that you should play these characters. It is an aesthetic. It’s a taste thing. It’s a practice. Having said that, I think the perception has changed massively and it’s now all part of the standard industry tool kit. Certainly, it’s not going to go away.
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How is preparing for roles like Gollum and Caesar different from preparing yourself to play a human role?
Obviously, there’s a physical vocabulary. That takes a lot of research and development. But at the heart are characters with real emotions, emotions that we relate to. Some are slightly more anthropomorphized and some are more animal. Caesar was very much a blend because he’s a being that is trapped between the human and animal world. Kong was more gorilla-like. Gollum used to be humanoid and has become physically wrecked by his addiction to the ring. So they’re all psychologically driven characters. And I think that is the thing that people misunderstand. They think that you’re just going to learn how to do monkey movements. Really that’s the last thing. It’s starting from the position of understanding a character like you would a live-action character, in terms of its emotions, its needs, wants, desires.
You’ve mentioned in other interviews that people are always doing their impressions of Gollum for you. Is Gollum something that haunts you?
[Laughs] Gollum is my picture of Dorian Gray. He will be with me for the rest of life, and I will grow to look more like him as I get older.