Planned but never produced, Star Trek: Phase II was set to air in 1978. It would have put most of the original crew back onto the Enterprise for a second five-year mission. Leonard Nimoy did not agree to return as Spock, and a full-blooded Vulcan named Xon was planned in his stead. Twelve episodes were scripted. However, partly due to the popularity of the recently-released Star Wars, Paramount decided to make a Star Trek movie. The series was scrapped; however the first script became Star Trek: The Motion Picture, while two others were eventually adapted as episodes of Star Trek: The Next Generation. (via Wikipedia)No tags for this post.