Talk show queen Oprah Winfrey has signed up for a guest spot on TV comedy 30 Rock in a bid to boost the show's flagging ratings. The Alec Baldwin and Tina Fey-starring sitcom is critically acclaimed, but has struggled to attract viewers - prompting NBC bosses to look for guest stars.

Winfrey shot her role at the weekend, and will appear in one episode on November 6. NBC boss Teri Weinberg says, "Oprah Winfrey's presence on 30 Rock makes this episode a television event. She is a true legend in her own time, and in this comedy's tradition, it provides the perfect showcase for stars of her renowned status. We are all thrilled."

30 Rock creator/star Tina Fey adds, "Oprah is very funny in the episode, and we are beyond grateful to have her. Also, I would like to announce that we are officially best friends."

(This news article provided by World Entertainment News Network)