Sixty felt like a big landmark. Not in a dreadful sense, but none of the other birthdays have bothered me. It's got labels on it - OAP, retirement - and I just wanted to take stock. I wanted to be in my greenhouse at home and at least give myself the opportunity of not working again.

I'll tell you how it happened. The phone rang. Paul, my agent, goes, 'Would you like to play Meryl Streep's?' I said, 'Yeeees! I'll do it, whatever it is.' He said, 'It's Mamma Mia!.' I said, 'Oh no, which character? The fat friend?

Everyone comes up to me saying, 'Cooee, Julie! Hello!' as if I know them. Of course I don't bloody know them. Am I flummoxed by it? Sometimes. I think, 'Ooh, love, go easy.' For a time, I did feel this pressure that I had to be funny, but it passes.

It seems that when you get to a certain age you almost give yourself permission to misbehave and say what you think. People allow it, with very old people.

That's why I'm an actress - escaping into a world.

There is this idea that appealing to youth is the only way forward. But that is no longer the case. Youth is not everything. Now we have all the baby-boomers in their 60s, like me, who are actively engaged in life - we're not retiring, we're not just being put out to grass once we hit 60.

The way I relax is I think, 'I haven't got anything coming up.' I like to know there are months ahead when I've got nothing.