When it comes to Star Trek, the numerous films over the decades have been hit or miss. Many fans agree that the second film, Wrath Of Khan, is the greatest hit of them all. It is the one that is referenced the most, and it even managed to create new generations of fans.

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Looking back on the films featuring the original series cast, though, many fans have begun to take notice of the sixth and final film of the TOS era, The Undiscovered Country. In many ways, this film serves as a finale to the original series and is arguably the best story to come from that era. Each film is beloved by fans, and each fan has their own arguments as to which is the best in the series.

Wrath Of Khan: Brought Star Trek Back To Its Roots

A USS Enterprise scene from The Wrath of Khan

For over a decade, Star Trek was the biggest name in science fiction. That is until 1977 when two were similar enough to earn comparisons, but the newer film seems to be the most popular. A revival of the classic series had been in talks for years, and this was the perfect opportunity to do so, thus Star Trek: The Motion Picture was released in 1979.

The film attempted to be the more adult of the two franchises and was criticized, by some, for being boring and essentially ripping off 2001: A Space Odyssey. The filmmakers realized what made Star Trek so beloved was its fun and campy nature, so in 1982, Wrath Of Khan was released to high critical and fan praise and reminded everyone what made a good Trek story.

Undiscovered Country: It's Serious Tone

Kirk and Bones stand trial in Star Trek: The Undiscovered Country.

In the late '80s, Star Trek made its triumphant return to television with Star Trek: TNG's best episodes, something Undiscovered Country took from.

The sixth film was released after TNG had begun airing, so the more serious tone was already welcomed by Trek fans. The film dealt with political undertones and themes of assassination and showed a side of Captain Kirk fans had yet to see. And as different as this film was, it was still Star Trek at its heart.

Wrath Of Khan: Served As A Sequel To A Classic Episode

Space Seed episode of Star Trek showing Khan's first appearance, wrestling with Kirk over a phaser.

One of the most famous and beloved episodes of the original series was "Space Seed," which aired during its first season. The episode revolved around the Enterprise crew finding Khan, a superhuman who attempts to take over the ship and use his army to rule.

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The episode ends with Khan being marooned on a deserted planet, which is where he is at the start of Wrath Of Khan. The film does a good job at reintroducing a classic villain and shows that his titular wrath has been a long time coming. He has grown stronger and much more dangerous than the last time fans saw him, which fits with the older and wiser Captain Kirk.

Undiscovered Country: Shows Both Sides Of Kirk's Dilemma

Kirk ponders what is right and wrong in Undiscovered Country.

A key plot point in Undiscovered Country is the Klingon's wish to make peace with the Federation, something James Kirk is not too thrilled about. But instead of showing Kirk as a hateful bigot, the film explains why Kirk is hesitant to go along with this, and even shows his willingness to be open.

For years, Captain Kirk has fought with the Klingons, and his hatred stems from them taking his son from him. The film even shows how willing the Klingon council is, if not for one bad seed that frames Kirk and sets the film's plot forward.

Wrath Of Khan: Shows A Fierce Rivalry

Kirk screams Khan's name in an iconic, yet silly scene

Khan's only goal in the first Trek sequel is to make Kirk suffer. He will do whatever it takes to do this, and Kirk will do whatever he must to stop him. This hatred for the main character makes Khan a brutal villain fans love to hate, although his lust for vengeance is not completely unwarranted.

The film does not make Khan out to be a cut and dry villain and instead shows what made him be this way, and why Kirk may have been in the wrong all those years ago. Captain Kirk is a flawed man, and the film does not hesitate to show this, yet everything he does is for the good of his ship, even if it means unintentionally nearly wiping out a race of people.

Undiscovered Country: It's A Good Mystery

Spock discovers the truth in Undiscovered Country.

While Kirk and Bones stand trial for a crime they did not commit, Spock realizes that this framing may have been an inside job. The subplot of Spock and his crew searching the Enterprise for a mole is everything a good mystery should be. It has twists, turns, and enough clues to keep the audience guessing.

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A mystery such as this fits well with the tone of the film, and while intriguing, does not derail the main plot at all. The conclusion may not be incredibly surprising, but it is the means of solving the mystery and the satisfaction of justice that makes it all worthwhile.

Wrath Of Khan: The Family Dynamic

Kirk's son, David Marcus in Wrath of Khan looking off camera and smiling slightly.

Wrath Of Khan reveals that sometime between films, Kirk fell in love and had a son. He is shown to not have been the best father, as his one true love has always been exploring the stars in the Enterprise. Wrath Of Khan has Kirk confront his son, and he soon realizes there is more to life than trekking through the stars.

Fans understand why his son is cold toward Kirk, yet it is still satisfying to see the two reconcile and make up for the lost time. Kirk having a son makes the film's stakes all the higher and adds even more suspense to an already quite suspenseful film. Khan blames Kirk for the loss of his family, and this makes Kirk realize just how important family is.

Undiscovered Country: Ties The Bridge Between TOS and TNG

The Enterprise crews of TOS and TNG in two side by side images.

By the time the sixth film came out, The Next Generation was just as popular as its predecessor. And The Undiscovered Country does a great job at bridging these two eras. Not only does the film feel similar in tone to the show, but it also marks the official end of the original series, bringing it all to a close.

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The film further bridges the gap, by having Michael Worf play a relative of his TNG character, Worf, in a cameo appearance. A lot has changed in the years between shows, so it is nice for fans to see how one era ends and another begins.

Wrath Of Khan: The Final Sacrifice

Spock's funeral after giving his life to save the ship in Wrath of Khan.

One of the most heartbreaking and iconic moments in any Star Trek media is when Spock sacrifices himself to save the Enterprise in an emotional scene. While he did return in the following film, to many, this was the shocking end of one of the most beloved characters of all time.

The original plan was to keep Spock dead, and the somber ending to the film shows this. The character was introduced as a man of science devoid of all emotion, and this sacrifice proves he was more human than anyone and deeply cared about his friends and his ship.

Undiscovered Country: It's The Perfect Swan Song

the original crew in their final adventure together

Even while TNG was in its early years, fans could still enjoy the original cast in the theatrical films. The sixth film was going to mark the official end of the OG Enterprise crew, however, and this was bittersweet to most.  On one hand, the films were not doing as well as they once were, but on the other, it was sad to say goodbye to these famous and beloved characters.

The film even ended with the signatures of the main cast appearing on screen, something another movie did withAvengers: EndgameThe film wrapped up the story of these characters perfectly and ended the decades-long journey on a high note.

NEXT: 5 Best & 5 worst Star Trek Crew Of All Time, Ranked