Being longer than a Star Trek TOS series episode, this movie still shares a ton of DNA with it's originating series. Once again, we find the Enterprise and it's crew against a mysterious and very destructive entity and see them overcome it with logic and reasoning and bravery too.
This, if it was a normal episode wouldn't have me put it as compelling as "Charlie X", "Where No Man Has Gone Before" or even the episode with two Kirks which I have forgotten the name of but undeniably it presents an interesting, curious set of events that have very value of a classic sci-fi story. Which is a shame because I feel like it was a little under-handed, possibly because even in a normal Star Trek episode we have more causalities and tension than in this entire movie but it's not without it's merits.
For one, the movie knows it has a higher caliber of visual fidelity and special effects and uses it to it's utmost by often showing us exteriors of an object or the Enterprise for minutes just so we can visually feast on it. The effects barring the astronauts that looked awkward floating in space, all look brilliant and very imaginative.
This is a must-watch for anyone watching the TOS series because it's essentially at its best, more Star Trek. Though it may not reach the character-driven complex narratives of a series like Deep Space Nine
Every TOS movie was great in its own way. Yes, even #5, for two reasons. First, the Kirk/Spock/McCoy dynamic was as good as it's always been. Second, because the antagonist was that best kind of antagonist - the kind who thinks they're the hero of their own story.
It was good only because of the cat lady with three boobs.