Who stopped Nichelle Nichols, who played Lieutenant Uhura on "Star Trek", from leaving the popular TV series?

Nichelle Nichols (b. December 1932 in Robbins, Illinois) is an American actress, singer, and voice artist best known for her portrayal of Nyota Uhura in "Star Trek: The Original Series", and its film sequels. Nichols' portrayal of Uhura was groundbreaking for African American female characters on U.S. network television.

On Star Trek, Nichols became one of the first black women featured in a major TV series. Her prominent supporting role as a bridge officer was unprecedented. During the first year of the series, Nichols was tempted to leave the show, because she faced unfair treatment and wanted to pursue a Broadway career. It was a conversation with Dr. Martin Luther King Jr. (1929—1968), a civil rights legend from 1955 until his assassination in 1968, that changed her mind.

She has said that Dr. King Jr. personally encouraged her to stay on the series, telling her that he was a big fan of "Star Trek". He said she "could not give up" because she was playing a vital role model for black children and young women across the country, as well as for other children who would see black people appearing as equals, going so far as to favorably compare her work on the series to the marches of the ongoing Civil Rights movement.

The response by Dr. King Jr. left Nichols speechless, allowing her to realize how important to the civil rights movement her role was. She subsequently met with Gene Roddenberry (the show's creator) in his office to tell him that she would stay.