Keira Knightley thinks it is "exciting" that her career could quickly come to an end.

The 25-year-old actress is thrilled to have fulfilled her ambition of becoming a movie star but claims she also loves the uncertainty of her profession, in that she could suddenly find herself out of favour with casting directors.

She said: "All through my life what I've loved doing is watching movies. I love the escapism of film, I love stories. So it is incredible to be able to be in them as much as I am, to see them from the first stitch in a costume to the end product. That's what I find really incredible and that's what I've always wanted to spend my time doing.

"But acting is very much a profession that is you're hot one moment and not the next - and that is totally cool. I think that's what I find most fascinating and most exciting about it - is that it can be gone in a puff of smoke."

Despite facing an uncertain career, the 'Never Let Me Go' actress insists she wouldn't like to be given the chance to find out what the future holds.

She added to "If I was offered a glimpse into the future, I think I'd refuse. I don't want to know. What if it was awful? Or what if it was really good? I mean, no. Either way, it's gonna be awful because if it's really good, then you're expecting it and therefore it's not as good as you thought it was gonna be. And if it's really awful, then you're dreading it and then you spend your whole life dreading it. That would be awful. Definitely not into that."