Even if you aren't a huge fan of the franchise, you have to appreciate the show where it all started. There are a myriad of science fiction shows on streaming services in this day and age, but in the 1960s, Star Trek: The Orginal Series was something new.
The show left an endearing legacy that still echoes in modern entertainment. For a reminder of what made Star Trek TOS so special, here are the most highly rated episodes according to IMDb.
The Devil In The Dark - 8.4
"There's nothing more dangerous than a wounded animal," Kirk asserts near the beginning of this episode. By the end, he is proven wrong by an angry mother animal. The moral of this story is that things aren't always as they seem, and that fear and ignorance can cause people to do stupid, destructive things unless a few intrepid space explorers are on hand to save the day.
The Enterprise Incident - 8.5
This episode was based on a real-life incident involving an American military ship and the North Korean government. It's the political intrigue and personal drama that make "The Enterprise Incident" an exciting episode. Even the viewer is left in the dark during this tale of Starfleet espionage. It's also fun to see Spock get all the attention instead of Kirk for a change.
Journey To Babel - 8.6
A fan favorite that gives the viewer more backstory on Spock specifically and Vulcans in general, "Journey to Babel" was a colorful episode that set Star Trek apart from other shows of the time. We're also introduced to Amanda Grayson and her husband Savek, popular characters who appear in a variety of future Star Trek series.
"Journey to Babel" has a bit of everything that makes TOS great. Creative and interesting aliens, political tension and resolution, personal drama, and high-stakes adventure.
Amok Time - 8.7
Speaking of Vulcans, this was the first episode that featured their home planet along with some of its most prominent leaders. T'Pau, for example, would appear again in the film Star Trek III: The Search for Spock. Viewers love this episode because it gives us more information on the popular character if Spock, not only more about his personal life and inner feelings but also regarding his background and culture.
The Doomsday Machine - 8.8
This episode is just as uplifting as the title suggests. "The Doomsday Machine" begins with the tragic loss of a starship crew and several planets. An emotionally unstable then Commodore pulls rank and takes over the Enterprise in the midst of this crisis. The moral of this story is that authority figures with an ax to grind make difficult issues like mutually assured destruction even worse.
Space Seed - 8.9
The character of Khan Noonien Singh was introduced in this episode, as was the lore regarding the genetic alterations that were all the rage on earth in the 1990s. The episode has an open ending, with Khan and his followers deliberately marooned on what seems like a peaceful planet. The Enterprise crew would return decades later to find where their good intentions had led them.
"Space Seed" was a popular Star Trek TOS episode decades before it inspired one of the best movie sequels of all time. A franchise of movies and TV shows later and this is still one of the most iconic Star Trek stories of all time.
The Trouble With Tribbles - 8.9
With nary a battle or action sequence, unless you count that fight in the bar, it might seem strange that this episode is so popular. Perhaps it's because you don't have to be a Star Trek fan to enjoy the humor and intrigue. Virtually every character gets some screen time, too, revealing something about themselves through their positive or negative opinion of tribbles.
Balance Of Terror - 9.0
"Balance of Terror" is one of the few TOS episodes that give the viewer a glimpse of the Romulans and their culture. It's the very first episode where Romulans actually appear, making it historic and compelling even if you're not into Star Trek lore. Mark Lenard, the actor who appears as Sarek in "Journey to Babel" also appears in this episode.
Mirror, Mirror - 9.2
It was the first time that one of the main characters in a Star Trek show would visit the Mirror Universe, but it would not be the last. Viewers saw the cruelty and greed of the Terran Empire, a foreboding example of what Starfleet could become under different influences.
The concept of an "evil" Starfleet was intriguing, and what the episode lacks in special effects and different set pieces it makes up for with costuming, writing, and some decent acting. Check out modern Star Trek shows like Discovery to see this concept taken to a whole other level.
City On The Edge Of Forever - 9.3
A classic that's been revered, parodied and outright copied for decades, "City on the Edge of Forever" combines all the best Star Trek tropes and features the most popular characters. Spock has some great lines in this episode, lamenting his lack of modern equipment, and Kirk actually comes across as a sympathetic character.