MOVIE URBAN LEGEND: Leonard Nimoy turned down a chance to appear in and direct Star Trek: Generations due to how little Spock's dialogue sounded like Spock to him.
Star Trek: Generations was the "bridge" film, as it appeared between the final film to star the original Star Trek crew (Star Trek VI: The Undiscovered Country) and the first film to start the Star Trek: The Next Generation crew (Star Trek: First Contact).
The film mostly centered around Captain Kirk meeting the Next Generation crew after an accident in the beginning of the film had seemingly killed Kirk, but really trapped him in a "Nexus." When he emerged, it was the future and he teamed up with Captain Jean Luc Picard.
As you might imagine, this film had been highly anticipated as soon as it became apparently that the Next Generation TV series was going to be coming to an end, but initially they had plans for a more straightforward team-up of the original crew with the new crew.
That fell by the wayside and the script was re-written so that it would concentrate on just the "Big Three," Kirk, Spock and McCoy...
The issue, though, was that the film was REALLY just about Kirk, so Spock and McCoy were practically glorified cameos. Therefore, even though Nimoy was offered the chance to DIRECT the film, he said he wouldn't do it unless they beefed up his role. As he recalled later on, "I said to everybody concerned [...] that if you took the dozen or so lines of Spock dialog and simply changed the name of the character, nobody would notice the difference."
So Spock was out and health issues pushed DeForest Kelley out of the film, as well. Scotty and Chekov were the replacement characters...
And speaking to Nimoy's point, Scott's lines in the final film were almost EXACTLY the same lines as Spock's were before they changed characters, despite the characters obviously being much different from each other.
The legend is...
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