Harve Bennett, who produced the second through the fifth Star Trek films based on the Original Series, had a plan in mind for the sixth film. Instead of creating a movie based upon the cast at their current ages, he wanted to focus on the early years with the film named Star Trek: VI The Early Years.
Bennett had the idea to cast John Cusack to play young Spock and Ethan Hawke to play Kirk in their days as teens at Starfleet Academy. He even made the offer to the two actors about the project which would have also included Dr. McCoy who joined the academy to put his past behind him. Kirk, having lost his true love, would have been a womanizer who was commitment-shy. And we would have gotten the chance to see the relationship that formed between Kirk and Spock with William Shatner and Leonard Nimoy providing wraparound narration much like they were looking back on the past.
This idea was planned at the time that coincided with Star Trek’s 25th anniversary so it ended up being scrapped because the producers instead decided to bring the original crew back together for one last swansong which, in turn, became Star Trek: VI: The Undiscovered Country.
While the 2009 version of Star Trek went into some detail about how Kirk and Spock met, I think it would have been far more interesting to have seen Harve Bennett’s version as he knew the original characters and had written for them before. And with the added bonus of Shatner and Nimoy providing narration, it would have made for a great in-between movie or perhaps even after The Undiscovered Country as a way to wrap up their experiences and lives.
For several years after The Undiscovered Country, Harve Bennett still had interest in the idea, saying back in 1996 that he would “make it in a minute if I had the chance.”