'Crazy' actress Keira Knightley

Keira Knightley says actress shouldn't be role models because they are too "crazy".

The 'Duchess' star - who plays Georgiana, the Duchess of Devonshire, in the new period drama - insists young women should not be influenced by film stars because they will get the wrong idea about how to act in life.

She said: "You have to leave your emotions available to you. Which is why all actresses are crazy and why I don't particularly think they should be role models."

Keira also revealed she "expects" to star in bad films, because you can't have a trouble-free film career.

She added to the Big Issue magazine: "You never know what is going to happen. You can have the best script, the best everything and the film can still be c**p. Or you can still have c**p people and the film, for some reason, can still be good.

"So you have to accept that failure is going to happen - and it is going to happen - and I'm going to make shocking films and do really horrendous performances. It won't be intentional, obviously!"