Who played the original Number One in the unaired pilot 'The Cage'?

Majel Barrett played the original Number One in the unaired pilot “The Cage.”

Number One was the cool, highly logical first officer serving under Captain Christopher Pike aboard the USS Enterprise. Gene Roddenberry wrote the role specifically for Barrett, who was then closely associated with him personally as well as professionally. The character’s senior position made her unusually prominent for a 1965 television science-fiction pilot.

NBC rejected “The Cage,” and Number One was omitted from the second pilot and the regular Star Trek cast. However, much of the pilot was reused in “The Menagerie,” broadcast in 1966, which brought the character into the franchise’s continuing story. “The Cage” itself was not broadcast until 1988.

Barrett later became better known in Star Trek as Nurse Christine Chapel and as the voice of many Federation ship computers. Rebecca Romijn eventually played the same character in modern productions, but she did not play the original pilot version.