At 19, you know everything; by the time you're 40, you haven't got a clue.

You have no idea what's going to happen [in Downton Abbey] until you get the script. We roughly knew a couple of the key points that were going to happen, but when I got the last episode, I turned to the last page to check that I was still alive.

It's never happened to me before, in my career, and never will again. It's a one-off experience. It's a rare treat to have a cast together for six years. Crews come and go, and a few of them have been there throughout, but not many. It's rare, in my experience, after 26 years, to have had a proper company in a show that enjoys each other's company, and who is such a fine bunch of people and actors. To have struck a chord with people, and to have had that combination, is extremely rare.

In the age of the camera phone it's a bit weird when you're sitting having dinner in a restaurant and people think they're being very subtle taking a photo while in fact they're being very obvious. When you're in a middle of a mouthful with friends or family and people come up asking for a photograph, that's when you want to say, 'Actually, I'm going to say no; I'd like to finish my meal. This is my time.'

The press mainly want to destroy a program by revealing what's coming up. For some reason, soaps like doing that.

After World War II, the major estates really did collapse.

I've had people come up to me in the past and say they enjoyed whatever show I've been in.