Cumberbatch's Hobbit dance

Benedict Cumberbatch "danced on the roof of the world" during The Hobbit: The Desolation of Smaug.

The British actor voices the title dragon in Peter Jackson's fantasy sequel.

While shooting the movie in New Zealand Benedict was blown away by the scenery and couldn't resist busting some moves in an idyllic location.

"I went walking and I swam the glacial lake as well. Peter organised a helicopter ride as well, which I think is probably the most extraordinary experience of my life. We landed on the top of a glacier... I was in jogging pants, a T-shirt and a pair of trainers on the top of a glacier in an area inaccessible to humans by foot or climbing," he recalled to flicksandbits.com.

"So we were just on this very pristine and unspoiled glacier, hovering in a helicopter and it lands and I get out and I just danced on the roof of the world on a glacier, in my T-shirt, jogging pants and trainers. It was incredible. I've got a deep, deep affection for the country."

One scene in the film sees Smaug try and capture hobbit Bilbo Baggins, played by Benedict's Sherlock co-star Martin Freeman.

Benedict loved the intensity of the moment and witnessing the chase between the two characters.

"Smaug can't see this person that he knows is in his space, but he can feel that he's there and he can smell him and he can hear his breath - his senses are highly, highly tuned," he explained.

"He's a hunter and a predator. He's got this mouse in his cat's lair, you know? He knows there's something there for him to have fun with. There's some fantastically, dark, drama there - and humour. The whole thing is an epic odyssey."