Rachel McAdams is ''haunted'' by her 'Mean Girls' character ''every day.''

The 39-year-old actress portrayed the role of mega bitch Regina George in the teen comedy in 2004 but has admitted, although she's gone on to star in a number of other highly successful flicks, she's best known for playing the blonde bombshell.

Speaking to the New York Times newspaper, she said: ''Does Regina George haunt me every day? She does have that quality. No, I have to thank Regina George for giving me some longevity. I'm forever grateful to Tina Fey and Mark Waters.

''I remember when I read it [the script], I called my agent right away and said, 'I will play any part in this, please, please, please.' I was at the beginning of my career, and it was a lofty thing out there, that I really, really, really wanted to do.

''I'm always looking for larger-than-life characters, which is probably why I like playing villains. They get away with so much.''

And the 'Notebook' star enjoyed the role so much that she recently offered to be an understudy in the 'Mean Girls' Broadway show.

She said: ''I really hope I get an invitation, yeah.

''I would love to see it. I'm so, so curious about it.

''I'll be the understudy. I just hope Regina George never gets sick.''

Regina will be played on stage by Broadway veteran Taylor Louderman and creator Tina Fey recently proclaimed her to be the perfect choice for the role.

She said: ''Taylor Louderman not only has this giant voice and great comic timing, but she instinctively understood the idea of Regina George, that there's power in making people come to you.

''She knows exactly when to play things really small, and there's so much power in it, and I think she's at times so wonderfully scary but so funny.''