Top 10 Episodes From Star Trek The Original Series

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Okay, creating a “best of” list for Star Trek: The Original Series is always a fun, yet challenging task, as opinions will certainly vary! However, taking into account popularity, critical acclaim, influence on the franchise, and cultural impact, here’s my attempt at a Top 10 list of the best TOS episodes, starting with the best:

Top 10 Episodes of Star Trek: The Original Series

1. “The City on the Edge of Forever” (Season 1, Episode 28): This episode is widely regarded as not just the best of TOS, but possibly the best of all Star Trek. Harlan Ellison’s story is a tragic masterpiece, exploring love, loss, and the immutability of history. Kirk must make an agonizing choice when a time-traveling McCoy threatens to alter the timeline. Edith Keeler’s fate remains one of the most heartbreaking moments in the franchise.
2. “Balance of Terror” (Season 1, Episode 14): A tense, submarine-style thriller that introduces the Romulans. This episode showcases Kirk’s tactical brilliance as he engages in a deadly cat-and-mouse game with a Romulan commander. Mark Lenard’s performance as the Romulan commander is legendary, making him one of the best one-off antagonists of the original series. The exploration of prejudice and mutual respect between enemies is powerful.
3. “Space Seed” (Season 1, Episode 22): The introduction of Khan Noonien Singh, played magnificently by Ricardo Montalbán. This episode lays the groundwork for Star Trek II: The Wrath of Khan and remains a classic. The story explores the dangers of genetic engineering and the allure of power, with Khan’s charisma and ruthlessness making him a truly memorable villain.
4. “Amok Time” (Season 2, Episode 1): Our first glimpse into Vulcan culture and Spock’s background. The episode delves into the Vulcan mating ritual, pon farr, and features an intense fight between Kirk and Spock. The episode is filled with iconic moments, including the famous “live long and prosper” salute and the fight theme music (“The Ritual/Ancient Battle/2nd Kroykah”). It introduced key elements to the Vulcan lore.
5. “The Doomsday Machine” (Season 2, Episode 6): A thrilling adventure featuring a massive, planet-consuming weapon of unknown origin. The episode is full of suspense and action, as the Enterprise crew races against time to stop the doomsday machine. William Windom delivers a powerful performance as the traumatized Commodore Decker, further adding to the emotional depth.
6. “Mirror, Mirror” (Season 2, Episode 4): The introduction of the Mirror Universe, a darker, more brutal parallel reality. The episode is a fascinating exploration of good and evil, with the “evil” versions of the Enterprise crew being both terrifying and captivating. The Spock with the goatee became a pop culture icon!
7. “Journey to Babel” (Season 2, Episode 10): This episode introduces Spock’s parents, Sarek and Amanda, and further develops the strained relationship between Spock and his father. It also features intrigue and a murder mystery involving various alien species. The episode provides important insight into Spock’s character and the complexities of Vulcan-human relationships.
8. “The Trouble with Tribbles” (Season 2, Episode 15): A lighthearted and comedic episode that has become a fan favorite. The Enterprise is overrun by rapidly multiplying, furry creatures called Tribbles. This episode showcases the crew’s lighter side and features memorable moments, like Kirk being buried in Tribbles. It’s a delightful break from the more serious episodes.
9. “A Piece of the Action” (Season 2, Episode 17): Another comedic gem, this episode features the Enterprise crew dealing with a planet that has modeled its society after 1920s Chicago gangsters. The episode is filled with humor as Kirk and Spock attempt to navigate this bizarre culture. William Shatner’s over-the-top gangster impression is pure entertainment.
10. “Errand of Mercy” (Season 1, Episode 26): The introduction of the Klingons, another iconic Star Trek race. The episode depicts the escalating tensions between the Federation and the Klingon Empire and introduces the Organians, powerful beings who force a peace between the two sides. John Colicos’ performance as Kor is memorable, setting the stage for future Klingon portrayals.

Honorable Mentions: “The Naked Time,” “The Devil in the Dark,” “Where No Man Has Gone Before,” “This Side of Paradise,” “What Are Little Girls Made Of?”, and many more.

This list is sure to spark debate, and that’s part of the fun of being a Star Trek fan! Each episode has its own merits, and the beauty of The Original Series lies in its diverse range of stories, themes, and characters. Live long and prosper!

Last update on 2026-01-02 / Affiliate links / Images from Amazon Product Advertising API