Ewan McGregor and I said this to each other after we saw The Ghost Writer. Every time Roman Polanski did a "No, no, no!," he was right. It was really as if a sculptor was asked to sculpt the embodiment of despair - that was the attitude he would strike. But as with every sort of inspiring teacher you ever had who was strict and scary, when you get it right, the sun comes out, and it's worth it.

There are movies where I've walked onto the set and felt, "This is home," and I'm confident in myself and my work, but that was my first experience of live TV. At that stage, Friends was at its unassailable height of popularity and brilliance.

I was lucky, because Ewan McGregor had already been shooting with Roman Polanski for about a month before I got role. And he did a faultless impersonation of what it was going to be like. So when direction happened, it was like, "Oh yeah. That's what Ewan said was going to happen." And so it was a little bit less debilitating than it might have been.

My skin may have wrinkles but it's because I'm smiling so much. That might sound like some terrible American greetings card, but I feel it's immoral for me to castigate my body for getting older, when it does everything I ask of it.

As I was getting into the helicopter, a slightly nervous actor said to me, "Whatever you do, don't say to the helicopter pilot, 'Show me what this baby can do.'" So I of course, got into it and said, "Show me what this baby can do." And we just had this insane helicopter ride. It's the sort of thing you only get to do on movie sets. I'm so lucky to have done it and have that chance.

I think it's quite lucky that I lead this lifestyle, and in fact, my career's only gotten better as I've looked older, because it ages you, the uncertainty.

My very first friend was my stand-in, who's a very dear friend to this day, and she kind of saved my ass. She told me where to stand and where the camera was and where to look. I thought, "If I don't enjoy this, then there's absolutely no point in being an actor."