Despite being nominated for three Academy Awards, Star Trek: The Motion Picture wasn't a fan favorite film. Though the cast of Star Trek: The Original Series were reunited onscreen for the first time in ten years, the movie wasn't the best it could have been for some fans. There were criticisms about the characters and how most of their time was spent staring at a screen. That was a concern for the actors, too.
In The Fifty Year Mission The First Twenty-Five Years by Edward Gross and Mark A. Altman, DeForest Kelley was quoted as saying "the characterizations were not there." He was worried about what this would mean to the film, and so were William Shatner and Leonard Nimoy. So the actors chose to intervene.
Kelley said "We had to put up a great fight. I think anyone will tell you that if the actors hadn't fought like hell to reestablish those relationships, they never would have been there. We would have had a special effects war." And even after the actors had something to say about the script, Kelley still didn't feel as though there was enough focus on the relationships between the characters.
"But Paramount didn't believe that the characters were as important to the public as they really were, and we couldn't tell them," Kelley said. Imagine taking Star Trek: The Original Series, a television show that got a lot of its energy from the focus on its three main characters, and turning it into a special effects only film that didn't care about the characters at all. That's what could have happened.
Even though many fans don't like Star Trek: The Motion Picture, thanks to Kelley, Shatner, and Nimoy, we got some reminders of the series that started it all, whether it was from the interaction between Spock and Bones or all three characters working in tandem. The film didn't rank as the best one in the Star Trek franchise, but it was the first one that brought the best team in Star Trek back onscreen. And for that, we will always be eternally grateful.