"It's a different rhythm than most movies. For a lot of the actors, you're 12,000 miles away from home. It becomes a way of life - getting up at five in the morning, shooting every day, day in day out, for 270 days. The new cast playing the dwarves were carrying incredibly heavy weights in their suits, they sat through hours of make-up every day. So it's quite challenging from a stamina point of view."