Star Trek VI: The Undiscovered Country
The Klingon Empire is predicted to collapse in 50 years, and the Federation is willing to talk peace. Kirk is sent as reluctant ambassador, but is just as soon framed for the death of Chancellor Gorkon. With he and McCoy in prison, Spock must unravel a widespread conspiracy.
Clearly all involved wished to end the film series on a higher note than the dreadful cacophony that was The Final Frontier, and they've succeeded. This does feel formulaic, but it's a formula developed from the better elements of the last five films, not precisely repeating any. Care was taken to make it not just a "last voyage" for the original cast, but a story with some significance to Star Trek history and to our own world. That said, the glasnost analogy is not subtle, but since the Klingons have always stood for Cold War enemies, it's an appropriate direction to take. Kirk's hatred is consistent with his attitude in TOS (Kirk views them as shallow villains), amplified by David's death. It's a struggle to overcome.
Spock has his own worries with the traitorous Valeris, one of the most memorable movie-only characters. The "murder mystery" elements keep suspense high throughout; again, a feat only The Undiscovered Country manages. The prison scenes are slowest, but we do see the harsh life into which Kirk and McCoy are (temporarily) forced. Fortunately Kirk and Spock don't linger on morbid thoughts for long. They've done life and death so often, it's good to see them squeeze all the life they can out of their last days together. Chang is no Khan, and we must agree with McCoy's "I'd pay real money if he'd shut up!" It's consider to place traitors on both sides. The supporting characters are back to contributing "cute moments", but they're not humiliating like those in The Final Frontier. Most admirable is the sense of finality paired with new beginnings, and that our beloved characters aren't "killed off," but fly into the semi-metaphorical sunset. A bittersweet end.
Themes: Forgiveness, acceptance, transition, the Course of Empire.
Production: This is the most fanciful film since the first. The dinner scene, with as Nimoy puts it, "punk Elizabethan" Klingon costumes, the trial, the journey across the frozen waste - all done with flare. It's a shame we don't see more of Klingon culture, and must wait for The Next Generation for more. Also fantastic is the score: moody, haunting, and punctuated in the right places. The main theme has an aged dignity in addition to the fanfare. An underrated soundtrack.
Spock: Nimoy definitely has his character back under his control, and there are several true developments of note, natural ones following The Voyage Home. The most obvious is his display of - gasp! - emotion. Most of the time he's still his cool self, but in critical moments, there is a surge of anger, sadness, or joy. When he knocks the phaser out of Valeris's hand, there is rage. The mind meld with her is as intense. He is wistful as he asks Kirk is they've outlived their usefulness. Hand-in-hand with the acceptance of human feelings is embrace human culture. From Nixon going to China to the Federation going to hell, he'll throw a curveball with an Earth reference. Apparently his "ancestor" is Sherlock Holmes, a fictional character, but then again, Spock is fictional too.
All anxieties about taking command are gone, and Spock can inspire the troops in times of trouble. It's convenient that the situation is a mystery requiring deductive reasoning, but Spock handles each aspect of running the ship impeccably, receiving not one complaint. He does, however, keep the Enterprise-A out of Federation control, against regulations. Another case of avoiding red tape for the greater good. He is glad when Kirk returns, having someone with which to share his misery over Valeris's betrayal. His diplomatic work prior film's beginning foreshadows his position as ambassador years later, seen in The Next Generation two-part episode Unification.