Emily Mortimer thinks voicing an animated car is the most "glamorous" role she has ever had.

The British actress voices sexy sports car Holley Shiftwell in forthcoming sequel 'Cars 2' and was relieved she didn't have to appear on screen because of her "bad" hair.

She said: "I'm convinced this is the most glamorous I'll ever be in celluloid on this film.

"And luckily I don't have any hair because my hair has always been my downfall. My hair looks really bad in all my movies so I was delighted to be a car that doesn't have hair. I look better in this movie than I ever have or ever will look in any other movie.

"Even my agent complains about my hair."

Emily's character is also an undercover spy but she insists she could never have based her portrayal on one of the glamorous women who feature in 'James Bond' movies.

She explained: "I couldn't do that because I knew if I tried to emulate a 'Bond' heroine I would just fall flat on my face.

"I just had to be me in that world. My natural instinct was to just do what I would feel, which is just completely dippy and pathetic in that situation and that's what I was doing.

"Then we realised that if she was out in the field, in this high-powered spy mission, she wouldn't be quite so c**p as that so we developed it together over time."