Science-Fiction would be forever changed when 1966 brought the future to the small screen. Star Trek, often dubbed Star Trek: The Original Series was a 3 season show in the 1960s that followed a utopian future captain and his crew in space. Star Trek: The Original Series was centered around Captain James T. Kirk and his crew aboard the USS Enterprise, as they explored strange new worlds, sought out new life and new civilizations, and boldly went where no man has gone before.

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The show is beloved by sci-fi fans, who often refer to themselves as “Trekkies”. With Star Trek being such an adored franchise, it’s entirely possible that some episodes of The Original Series go unnoticed, and are underrated compared to the other great episodes of Star Trek.

8 The Omega Glory, Season 2, Episode 23

star trek the omega glory

When the USS Enterprise arrives at the planet Omega 4, they discover the starship, USS Exeter, in orbit. Captain Kirk, Spock, McCoy, and Lieutenant Galloway all beam aboard, to find the ship completely abandoned, with only remnants of Starfleet uniforms and crystals remaining aboard the empty ship.

It’s another great Star Trek episode that delves into the importance and controversy surrounding the morality behind the Prime Directive. Kirk finds the captain of the Exeter aboard the orbiting planet, along with a primitive tribe, and delivers a great and inspiring recite of the preamble to the United States Constitution.

7 The Man Trap, Season 1, Episode 1

star trek the man trap

The Man Trap is the first episode of season one of Star Trek. It may not be the pilot for the show, but it was the audience’s first entry into this bold new world, and a vision for a future out of reach. The crew of the Enterprise finds themselves stalked by a creature that can assume any shape and form, killing for the salt content of its victims’ bodies.

For an introduction to what Star Trek had to offer, The Man Trap is the perfect starting point. It delves into the mystery, the relationship of the characters, and the true horrors that lie within the unknowns of space.

6 The Immunity Syndrome, Season 2, Episode 18

star trek the immunity syndrome

Well-deserved shore leave plans are put on hold from the crew of the USS Enterprise after Spock appears on the bridge stricken and informs both Captain Kirk and McCoy that the Intrepid, a starship manned only by Vulcans, has just “died”, with all members aboard. It’s not long before a long-range scan reports that the Gamma 7A system is dead, with billions of inhabitants.

It’s a classic sci-fi premise, with an intergalactic space being threatening the galaxy with its power. The crew aboard the Enterprise must deal with primitive life, which is growing exponentially thanks to the absorption of solar systems.

5 The Empath, Season 3, Episode 12

star trek the empath

The planet Minara 2’s sun is about to go nova. The USS Enterprise is sent to beam down on the planet and evacuate its inhabitants. However, they find the research station abandoned, and soon, find themselves at the mercy of aliens. These aliens use Kirk and his colleagues as guinea pigs in torturous experiments. However, the real victim is an empath who can absorb the pain of the victims.

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It's one of the show’s cheaper episodes, but it remains intriguing with an important message. The performances in this episode are great, with a true expression from the empath of pain. The scenes of torture are unnerving and rather difficult to watch.

4 Return To Tomorrow, Season 2, Episode 20

star trek return to tomorrow

This episode follows the three survivors of an ancient and unknown species, extinct for over half a million years. To seek immortality, and avoid infinite oblivion, these three survivors invade the bodies of crew members aboard the Enterprise and begin the process of building themselves android bodies. Their desperation for survival leaves them committed to acts they would otherwise not do.

It’s the pinnacle of quirky sci-fi fun, and to see the actors of iconic characters like Spock and Kirk portray themselves in such a different manner, is a refreshing treat. The episode also has a nice romance, with the alien threat being somewhat an emotional state of affairs.

3 All Our Yesterdays, Season 3, Episode 23

star trek all our yesterdays

Beta Niobe is set to go supernova. The crew of the Enterprise plans to go as a boarding party to warn the inhabitants of Sarpeidon, that their sun, is about to destroy their planet. Kirk, Spock, and McCoy beam down but find the building they are in empty, all except Mr. Atoz, a librarian in the library, with several of his replicas.

The episode deals with mystery, but one of the more important aspects of this episode is the central theme of love between Spock and the beautiful woman Zarabeth. Spock’s relationship with her conflicts with his Vulcan nature, to the point where he finds himself losing who he was.

2 The Changeling, Season 2, Episode 3

star trek the changeling

After receiving a distress call from the Malurian star system, the USS Enterprise finds itself receiving no response to hails on any frequency. Upon further research, Spock finds that his sensor data concludes a tragedy: four billion Malurians lack any sign of life readings in the system. Such an eradication of life leaves no time to mourn, as a large bolt of energy comes from nowhere.

The Enterprise is hurled around whilst on red alert and soon finds itself under attack from an old satellite. There’s a demonstration with great insight, but with questionable morality. The evolution from a known past makes for an interesting premise.

1 Friday's Child, Season 2, Episode 11

star trek friday's child

The crew of the Enterprise once again find themselves involved in power struggles, as they discover the problems arising on the planet, Capella 4. The Enterprise discovers that the Klingons want mining rights. With Scotty left in command of the Enterprise, Kirk, Spock, and McCoy beam down to solve the issues in person.

It’s another episode that focuses on the trio of Kirk, Spock, and McCoy, as they find themselves in a tough spot amongst the Klingons. Each character features their strength, and it shines in this underrated Star Trek episode.

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