Enterprise and the Klingon Empire
It's the same Enterprise we know and love, but it just feels...different. Darker. More claustrophobic. More tense. It's giving us shivers just thinking about it. And that's not even bringing up the sheer strangeness of hanging out in the Klingon Empire.
Director Nicholas Meyer made a series of choices that make Enterprise feel different from the way it felt in previous entries. Most notably, he reduced the amount of lighting aboard the ship and tightened the hallways. This is a way of both amplifying the film's dramatic intensity and giving it a more martial feel.
It also gives us a new view of the ship we know and love—even if it's not entirely pretty. While most entries in the Star Trek series depict the future as a utopia, The Undiscovered Country reveals that all of the prejudice and violence that plague us today are alive and well in the future. A big part of that driving that point home is making Enterprise feel less pristine than it has in the past.
The Upside Down
A similar effect occurs with the film's depiction of Klingon warships, which have a completely different feel from Federation ships. These monstrosities are even more darkly lit than Enterprise, and certain shots have a rolling fog in the background. It's like an Edgar Allan Poe story up in here. Aside from further emphasizing the film's martial tone, this strangeness also highlights the alien nature of the Klingon race.
The same could be said about our brief visits to Klingon society. For example, the courtroom where Kirk and McCoy stand trial is a huge, echoey hall, complete with cloak-clad judges. It's half Game of Thrones and half Battlestar Galactica. It's yet another way the film emphasizes the sheer strangeness of Klingons, with their culture that is built on feudal and even borderline medieval values.