Gary Oldman did the Cabbage Patch Kid dance and then sang a bit of John Lennon's "It Feels Like Starting Over" in his recent interview with HitFix. The veteran actor isn't exactly the quiet type -- having played roles from Sid Vicious to the "Dark Knight's' stalwart detective Jim Gordon to eccentric Sirius Black in the "Harry Potter" films.

But in "Tinker Tailor Soldier Spy," the 53-year-old English actor is, rather, serious, as British Intelligence agent George Smiley, making his way through a mole mystery in the early 1970s. He described Smiley's character -- and the film -- as "austere."

"It was a quiet focused set," he said, mentioning he arrived every day "prepared and ready."

But when you're surrounded by other esteemed talent and countrymen like Colin Firth and Benedict Cumberbatch, he couldn't help but to have a few silly moments. He described Firth as having a little twinkle in his eye. The days they shot scenes with many of the actors altogether in the agency "control room," it "was a lot of fun."

"It's refreshing to come in and play someone who's so restrained and quiet, and yet there's so much going on," he said, calling the acting job as Smiley as the perfect palate cleanser between projects.

Check out the rest of our video interview with Oldman, who's set next to play Elvis in "Guns, Girls and Gambling," Jim Gordon (again) in "The Dark Night Rises" and Floyd Banner in John Hillcoat's "Wettest County."