Second films are, you know, like 'difficult second albums', so it's a tricky position to be in but I think he's made a highly accomplished film.

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.

Everybody thinks performance capture is about thrashing around and doing a lots of movement, but it's actually about being able to contain and think and be believed in a close-up, as much as anything else.

I've done a fair amount of that stuff... when we did 'Lord of the Rings' the transformation sequence from Smeagol to Gollum was a 19-hour make-up job. You have to have a kind of zen button that you press and allow the mind to be focused in a certain way.

We've never had nannies. We've had great grandparents, great support from family, and the kids have been on every set: they've seen me play Gollum, King Kong, Captain Haddock, the lot. They totally get it, and they want to go into the business. Ruby, my daughter, is very keen to become an actress.

I am a bit evangelical, I know, but performance-capture is still misunderstood.

I think there will always be a particular generation of actors who think that they're going to be replaced by robots. But certainly the emerging actors understand that that's part of the craft.