Star Trek Phase II
Star Trek Phase II was a planned television series set to air in Spring 1978 on a proposed Paramount Television Service (which eventually became United Paramount Network) based on the characters of Gene Roddenberry's Star Trek. The planned series was to describe the adventures of the Enterprise crew on a second five-year mission after the completion of the first series.
Leonard Nimoy was conspicious in his absense
The series was planned to have included William Shatner and DeForest Kelley reprising their roles as James T. Kirk and Leonard McCoy. Conspicuous by his absence was Leonard Nimoy, who declined to return due to a marketing issue over the Spock character and obligations to the play Equus.
The series would have included several new characters, such as Commander William Decker, Lieutenant Ilia, and the Vulcan Lieutenant Xon.
Cancelled in favor of the first movie
Despite the completion of most of the sets, several television grade models (Including the Enterprise herself and many of the pilot episode's models), and twelve full scripts, plans for a series were cancelled in favor of a movie - Star Trek: The Motion Picture - in which all of the characters made an appearance (however briefly). Decker and Ilia appearred as major characters throughout the movie. Lieutenant Xon (now called Commander Sonak) appeared only for a few minutes and had a few lines of dialogue before being killed in a transporter accident — the actor who was to play Xon, David Gautreaux, made a cameo appearance in the same movie as Epsilon 9's Commander Branch.
At one early stage, Xon was given the name Savik. A variation of the name, Saavik, was later given to a female Vulcan in Star Trek II: The Wrath of Khan.
Two of the scripts were rewritten for movies
Two scripts for Star Trek Phase II ("The Child", "Devil's Due") were rewritten for use in Star Trek: The Next Generation due to a writers' strike. Additionally, some of the new elements in the series were eventually adapted into TNG. Riker may be seen as a version of Decker; and Troi of Ilia.
Due to the decision by Paramount Pictures and Roddenberry that only live-action events seen on screen qualify as canon, plus the fact that major elements including two episodes were incorporated by other Trek series, nothing involving Star Trek Phase II is considered canon. This creates some complications since many sources suggest that a second five-year mission of exploration - intended to incorporate Phase Two - occurred after TMP. However, there has never been any on-screen reference to Kirk being assigned such a mission, so unless a future TV series or film says otherwise, such a mission can only be considered fanon speculation.
Fanon is a fact or ongoing situation in fan fiction stories related to a television program, book, movie, or video game that has been used so much by fan writers or among the fandom that it has been more or less established as having happened in the fictional world, but it has not actually been established as having happened on the show, book or movie itself.
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