[on being asked what it's like to perform in front of a green screen] I took Green Screen 100. It was the class right after lunch on a Thursday. And that's seen me through. No, honestly, there is no training for it. I think experience is probably the best preparation. I get a second take which is always useful when I blow the first one. You rely on your director to have your back. We rely on our collective imaginations to envisage that the creature we're looking at is actually there, taking up space, so close you can probably smell it, I've had several interactions with these creatures.