Cynthia Nixon to appear on 'Big C'

NEW YORK, June 24 (UPI) -- U.S. actress Cynthia Nixon has signed on as a guest star for four episodes of the new dark comedy series "The Big C," Showtime said.

Nixon will play Rebecca, a "flaky, long-lost college roommate" of the character played by series star Laura Linney, who "re-enters her life and shakes things up in a wild way," the cable network said.

The 13-episode series is currently shooting in Stamford, Conn., for an Aug. 16 premiere.

Nixon is best known for her work in the "Sex and the City" television series and movies.