Julianna Marguiles wears a wig for her role on 'The Good Wife' as Alicia Florrick, she admitted on 'The Writers' Room.'

Julianna Margulies has a lovely head of black curly hair in real life but on "The Good Wife," her character Alicia has smooth brown locks, thanks to a wig.

"The main reason, honestly, was because I wanted her to have a little bit of that WASP-y look to her," Margulies, 47, said to E! Online, "and I'm a Jew with curly hair."

Margulies would have had to straighten her hair every morning for the role, which would have added another two hours to the makeup chair. The 'ER' actress prefers to spend the extra time with her husband, Keith Lieberthal, and their young son, Kieran.

Margulies' wig has been so successful that the 'Good Wife' actress has become a sort of CBS spokeswoman for wigs: CBS executives regularly ask her talk to other actors about the benefits of wearing a rug.

Margulies was part of an actress roundtable sponsored by The Hollywood Reporter on a recent weekend afternoon. The 'Good Wife' actress was joined by Homeland's Claire Danes, 35; Mad Men's Jessica Pare, 33; The Americans' Keri Russell, 38; American Horror Story: Coven's Sarah Paulson, 38; and Bates Motel's Vera Farmiga, 40.

She admitted that she was hesitant to take a role in the HBO hit series 'The Sopranos.' Margulies said, "I'm reading and reading, and suddenly [in the script] I'm in a bra and panties, doing heroin, and then I vomit."

Margulies also opened up about the most difficult phase in her life, saying, "[2002's] Ghost Ship. It had been written as a psychological thriller about what happens when you have too much of something -- money is evil, greed, and these two people start going crazy -- so I said yes! It was a big Warner Bros. picture. I was the lead with Gabriel Byrne. Then I got off the plane in Australia and the script had totally changed. Suddenly, I was in a really awful horror movie, and it was shocking."