Star Trek: The Original Series – Ranking Every Episode

The absolute bottom of the barrel. Few episodes of television have baffled me so completely like The Alternative Factor. The Enterprise comes across a man pinging backwards and forwards through time as he tries to escape an alternate version of himself. That sounds like a really compelling setup but the execution of this premise is baffingly inept. Lethargically paced with shoddy effects work and an aimless script, I found nothing to enjoy about this one. Star Trek: The Original Series could certainly offend more than this, but no episode was this dull.

The Omega Glory represents all of the thorny political and social dimensions to the Trek concept of a travelling Federation starship that most of the show manages to thankfully avoid. Through many episodes of Trek, there is an undeniable imperialist attitude with the mighty Starfleet and Federation laying down the law and expanding to the furthest edges of the universe. This episode plunges the crew of the Enterprise into a planet whose history almost mirrors our own, to a completely ridiculous degree, one that defies any believability, and which also positions the values of the United States as integral to peace and harmony on a galactic scale that rings so incredibly hollow. The whole episode carries the worst traits of this era of Star Trek and American television, propagandized sermonizing that reduces the wonderfully forward thinking and global setting of Star Trek to a ridiculous political sermon about the necessity for every civilization to take on American values.

At this point in Star Trek’s third season it was hard not to feel like the team had well and truly run out of ideas. Kirk loses his memory on yet another planet modelled after Earth and becomes a member of an indigenous community. It’s a good episode for showcasing Shatner’s talents, but there is really very little to hold onto here.

Any episode of television that centers around children always begins with apprehension for me, rarely has it ever resulted in quality, and sadly, Star Trek: The Original Series didn’t do much to counter that notion. A bunch of children with psychic powers try to take over the Enterprise and it’s about as terrible and irritating as it sounds. There is one moment however that I will never forget and that’s Kirk falling into Spock’s arms in the elevator, a moment that accelerated the homosexual undercurrent to their relationship to such an extent that it’s borderline impossible to believe its fan-fiction subtext.

Another episode focused on a group of mysterious children and this one doesn’t fare much better. Miri’s planet of mysterious deaths caused by aging into adulthood as a setup is interesting, but the borderline pedophilic relationship Kirk begins to develop with a child whose mind has grown far beyond her body is uncomfortable, misguided, and just plain boring.

The unfortunate final episode of the show also stands as one of its weakest. For a series built upon an optimistic vision of the future where humanity has progressed beyond prejudice to end on an episode that positions its villain as a woman trying to climb the hierarchical ladder. Turnabout Intruder’s brain swap episode has another fun, wacky Shatner performance, but the optics of its story and its treatment of the ‘hysterical’ Janice Lester is completely regressive for Trek, and it’s a shame this became the final statement of this wonderful series.

Truly nothing could prepare me for how bugnuts the premiere of Star Trek: The Original Series’ Season 3 would be, but perhaps nothing was better suited to demonstrate the series decline in the series final stretch of episodes. The setup is simple, some mystery woman zapped onto Enterprise and stole Spock’s brain, now they gotta go and get it. It’s an absurd premise and feels lightyears from the kind of contemplative, wonderful science-fiction storytelling found at the top of the list but I would be lying if I didn’t find some kind of charm in its campy nonsense.

One of the most uncomfortably dated episodes of Star Trek: The Original Series, A Private Little War is for all intents and purposes Vietnam in space. The Federation and Klingon Empire fight out a proxy war through the ‘primitive’ inhabitants of a planet that has begun to be armed by the Klingons. The allegory is both unsubtle and underdeveloped with the goals of each side feeling too simplistic to really make the story’s premise reach the moral ambiguity it is clearly aiming for. Instead A Private Little War comes off as stereotypical, reductive, and downright ignorant.

Oddly, one of the more fascinating episodes of the show while also being one of the least compelling. Assignment: Earth stands as the finale of Season 2 and a backdoor pilot for a spin-off show should a third season not be picked up by the studio. As such, most of this episode follows a whole new cast of characters centered around Gary Seven, a super intelligent, hyper competent mystery man trying to prevent nuclear war. The character of Gary Seven just never has much personality, and his world and supporting cast never hold much interest. It’s interesting to see a glimpse of a reality where this episode continued beyond Star Trek itself but I’m sure glad that’s not the one we live in.

My first introduction to Harry Mudd early into Season 1 was the first time I felt truly bored watching this show. The womanising mercenary’s pitstop on the Enterprise, with three mystery women in tow makes for a pretty tedious and sexist episode of the show, one of the few that places its social politics and attitudes squarely in the 1960s.

It’s fun to have Bones take the spotlight a bit on this one as he and Kirk come to blows over a pregnancy which could threaten the fate of the planet as the Klingons try to take it over. McCoy’s treatment of the pregnant Eleen is compelling and his complete commitment to her safety and wellbeing over any political motives speaks to his character more than almost any other episode. It’s just a shame that the rest of the story is dull, unfocused, and thematically muddled with a clear Cold War allegory that places the story and its politics firmly in its era.

Watching a little person ride on the back of William Shatner as he’s forced to parade around like a horse, I couldn’t help but think how far we had fallen from the profound, humanist science fiction writing of the show’s original season. Plato’s Stepchildren is another blatant attempt to reuse existing sets and costumes, with a group of all powerful beings who have modelled themselves after the teachings of Plato. This episode is made most famous for often being cited as television’s first interracial kiss, which when seen through the context of the episode is not much to really celebrate. The standout of the episode for me was the character of Alexander, who is imbued with genuine warmth and sincerity by Michael Dunn. His character and his relationship to the crew is immediately compelling and I certainly wouldn’t have minded if he had become a series regular on the Enterprise, it’s just a shame he couldn’t have found a home in a stronger episode.

The moment I realised that this was the series’ episode on hippie culture I braced myself. The Way to Eden certainly belongs down the bottom of any The Original Series list, but I was pleasantly surprised by some elements of the story to raise it in my estimations a little. The fact that Spock, the stoic, by the book man of logic is the most sympathetic to the freewheeling, emotional, and spirited space hippies was novel and elevated the story from simple farce to something a bit more intelligent and even handed. There’s an attempt made to demonstrate how emotion can give way to prejudice and while the quality of the episode and lack of focus means it stands as only an attempt I respect that they tried.

Another Season 3 snoozer without much to really write home about. After Enterprise encounters a group of glowing energy beings traveling through space, Scotty’s new girlfriend Mira plays host to them, slowly killing her as the crew try to find a solution where everyone can live. It’s just a fairly underdeveloped story and treads on similar ground to other, stronger episodes. As it is, this episode sticks out to me mostly for Mira herself who I thought was a great addition to the cast even if Scotty’s sudden infatuation with her feels rushed, but I would have loved to have seen more of her.

The Enterprise plays host to two rival peoples trying to build bridges through an arranged marriage between Elaan and her would be groom at the ship’s eventual destination. This being a television show from the 1960s, the gender politics of an episode about arranged marriage don’t exactly stand the test of time and while Elaan is an entertaining character she does fall into age old archetypes of exotic alien women using their powers of seduction to tempt powerful rulers. However, Elaan’s desire to run from her potential marriage and continue her warfaring ways is interesting, a princess bred to be a warrior who now has to play peacekeeper. That’s an interesting dilemma but the episode sadly settles into Kirk teaching an angry woman how to be civilised, there’s a good story in here somewhere but it just never had the chance to flourish.

Another interesting episode that falls into dated ideas about gender that rob the story of much of its impact and interest. The episode functions as a love story in the guise of a first contact narrative, with an alien being keeping famed inventor Zefram Cochrane alive in perpetuity completely isolated from the universe. The idea that an alien creature feels the emotional component of love but lacks the empathy to express it fairly is interesting but the script does little to expand on these ideas and instead this alien being is sent into a dying member of the Enterprise crew to live as a human companion for Cochrane. This ending completely robbing this character of her agency as her body is hijacked for an alien entity is one of the most disturbing endings in all of Star Trek: The Original Series, and the fact that the show doesn’t recognise it as such and even jokes about her being expendable only drags it further down the list.

Who Mourns for Adonais? finds the Enterprise encountering Apollo, who claims to be the very god worshipped by the ancient Greeks. The premise allows Star Trek to explore the idea that the gods of mythology may simply have been technologically advanced beings who were mistaken for divine figures, but the more interesting question is what happens when an immortal being demands to be worshipped in a universe that has moved beyond him. The interest of that concept unfortunately rarely manages to result too much within the episode itself, which settles into repetitive arguments between Kirk and this would be god, and a romantic interest for this Apollo which skirts into some uncomfortably dated territory.

One of The Original Series’ more unusual attempts at tackling overpopulation, The Mark of Gideon places Kirk on a seemingly deserted Enterprise before revealing that the ship is actually a carefully constructed replica designed to isolate him. The episode’s central idea is fascinating, as the Gideons have deliberately allowed their population to grow beyond sustainable levels and now see death as the only way to restore balance, creating a strange inversion of the usual Star Trek fear of disease and mortality. Kirk’s refusal to accept their solution gives the episode its moral centre, particularly as the Gideons have manufactured a deadly illness and intend to use his immunity to spread it through their population. The convolution of the narrative, its slow pace, and its unwillingness to truly explore its ideas makes it a real bore but it’s at least a bore that attempts to tackle a more serious social problem than many of its contemporaries.

Unfortunately, an episode where Kirk and crew are forced to fight in an alien gladiator arena ends up sounding a lot more fun than it is. The colourfully ludicrous costumes, vibrant production design, and insane action choreography positions The Gamesters of Triskellion as one of Star Trek: The Original Series’ camp classics. There is clearly an attempt to tell a story about slavery and exploitation, but these ideas are secondary to seeing Kirk kiss alien babes in bondage outfits. So there’s a certain charm to the episode but it’s far from the series finest hour.

This episode is admittedly complete and utter nonsense but it plays into several of my aesthetic sweet spots so I can’t help but wring a little enjoyment out of it. Seeing Kirk and crew pal around a big spooky castle is a fun enough time. Skeletons, giant cats, and dank dungeons, oh my!

The Apple takes the Enterprise crew to a seemingly perfect world where a primitive society lives under the control of a godlike computer called Vaal. The episode plays with the idea of paradise built on obedience, with the inhabitants protected from disease, aging, and even the dangers of nature at the cost of curiosity, individuality, and genuine human experience. The biblical imagery laden in the episode’s title and imagery is far from subtle, but it works surprisingly well as Kirk essentially becomes the serpent in Vaal’s carefully controlled Garden of Eden, introducing the idea that freedom and knowledge are worth the risks that come with them. There is also an interesting tension between the Federation’s desire to preserve life and the harsh reality that destroying Vaal will inevitably put the planet’s inhabitants in danger. The episode’s ridiculous depiction of this ‘simple’ tribe and the sheer bluntness of its messaging makes it a mess but its central argument that a safe life without freedom is not truly living fits comfortably within Star Trek’s humanist ideals.

One of The Original Series’ strangest episodes, Wink of an Eye takes the familiar idea of accelerated time and turns it into an unsettling story about what it would actually be like to live in a world where everyone else moves impossibly slowly. The episode carries an eerie feeling when the Enterprise is seemingly deserted, as Kirk discovers his ship has been infiltrated by beings whose speed makes them almost invisible to the normal crew. The episode does get increasingly ridiculous, particularly once Kirk is given yet another one-and-done romantic entanglement, but there’s something genuinely creepy about the idea of being trapped in a world where you can see everyone around you but they can barely perceive that you exist. It’s an inventive little episode that makes excellent use of a fun sci-fi concept.

Among the most disappointing episodes of the show for me personally. Kirk, Scotty, Bones, and various members of the Enterprise crew begin to age at a rapid rate after beaming down to a planet and coming into contact with mysterious, hazardous material. I was really excited about what this would mean for the crew as a ticking clock forces them to reckon with their own mortality and standing in the Enterprise’s chain of command as they fight against this unnatural flow of time. Bizarrely, the episode doesn’t explore any of the potent thematic material implied by its hook and instead devolves into a bizarre competency hearing with a senile Kirk yammering about meddling kids trying to take him away from the Enterprise. There are some fun performances but rarely has this show ever missed such a great opportunity to tell an exciting story.

The Enterprise discovers a civilisation housed within a hollow asteroid hurtling towards a planet, which is pretty out there as far as Trek stories go, but the episode finds genuine emotional weight in McCoy’s discovery that he has an incurable illness and his growing love for one of the asteroids inhabitants Natira, gives DeForest Kelley some of his strongest material in the series. However, its treatment of the planetoid’s society can be frustratingly simplistic, turning another strong idea into a rote and underdeveloped mess of halfbaked story concepts.

Perhaps the biggest disconnect in how limp an episode feels and how important the writing team obviously thought it would feel. Patterns of Force is another alternate Earth narrative where the Enterprise crew beam down to a planet to find a world modelled on Nazi Germany. It turns out that a Starfleet officer is the reason for this change as he sought to find an example of an efficient government in Earth’s history. The idea of a character trying to adopt supposed positive aspects of fascism while ignorantly trying to exorcise its evil aspects only to learn that the two cannot be separate is novel, but the episode plays into misconceptions around the Nazi’s efficiency and strength as a nation that makes this episode incredibly dated and naive.

As a massive Star Wars guy, one thing I missed coming into Trek was the lack of criminality, skullduggery, and general malice found in those seedier corners of that Galaxy Far, Far Away. So I was delighted to find an episode set in a space prison with space pirates running amok. It’s not a terribly novel episode, but Steve Ihnat as Fleet Captain Garth, in a performance one could only describe as the hammiest of sandwiches, is delightful.

By this point in Season 3, I couldn’t really say I was surprised when Abraham Lincoln flew onto the Enterprise’s viewscreen, but I was surprised that the episode was actually quite a lot of fun. Kirk’s fanboyish love of history makes this encounter with an assortment of random historical figures fairly enjoyable. I love the commitment to this universe by building out the ensemble with fictional historical figures placed alongside the familiar faces, some solid worldbuilding in this one.

As a big fan of the Batman show of 1966 I was overjoyed to find Frank Gorshin as the guest star of Let That Be Your Battlefield, as blunt an episode as there has ever been. Star Trek is not exactly a show I would call subtle, but an episode about two near identical enemies with black and white faces trying to kill each other stands as perhaps its most obvious allegory, if one could even call the subtextual sledgehammer at play here allegory. It’s obvious, but the two character’s refusal to see any commonality between them and the crew’s bewilderment at their predicament makes it a fairly fun and memorable piece of Trek.

Where it all began! The Man Trap is the very first episode of Star Trek to be broadcast to the world and already much of what has made this franchise so enduring for 60 years is here from the jump. Charming, kitschy production values with vibrant colours and imaginative imagery, a heightened, pulpy tone, and an altruistic futurist ambition mixed with bold and thoughtful science-fiction ideas are all here. While the franchise’s first adventure begins as a simple bid for survival against an alien monster, the episode reveals real depth and heart when the creature is revealed as the last surviving member of its species, creating an uncomfortable moral question about whether its killings are truly malicious or simply the consequence of an animal acting according to its nature.

One of The Original Series’ rarer, more character-driven episodes, Obsession takes what could have been a fairly straightforward monster of the week story and turns it into a surprisingly personal examination of Kirk’s guilt and obsession. After encountering a mysterious cloud that has been draining entire planets of life, Kirk becomes fixated on its destruction. This fixation eventually reveals a history where Kirk had failed to stop this menace before and his determination for vengeance and increasingly reckless behaviour puts the Enterprise and its crew at risk as they try to stop this threat and make it out alive. It’s not the most ambitious episode of the series, but its focus on Kirk’s psychology and the danger of allowing personal guilt to override reason makes Obsession a compelling little character study.

One of Trek’s pulpier episodes is complete with alien parasites and droves of red shirts beaming at tiny squids. Operation – Annihilate! won’t top anyone’s list of favorites, but I appreciated the worldbuilding with a thorough exploration of a planet colony and while this episode falls into familiar, fairly routine territory, there is certainly fun to be had here.

Another classic example of Star Trek turning a seemingly idyllic paradise into something considerably more complicated, as the Enterprise crew discover a colony of humans living in perfect health and bliss beneath the influence of mysterious spores. The episode works particularly well in allowing Spock to experience genuine emotional freedom, making his eventual decision to leave the colony far more poignant, though its simplistic solution and rather abrupt shift back to normality undermine some of its more interesting ideas. Still, between the striking pastoral setting and Nimoy’s bizarrely playful performance, it remains one of TOS’s more charming explorations of whether happiness is worth surrendering your individuality for.

I’m always going to be a sucker for kitschy studio sets covered in fog, the kinds of aesthetic found in Universal and Hammer horror films, so I definitely got a kick out of the moody visual design of this episode. Wolf in the Fold kicks off after Scotty is framed for murder while Spock and Kirk try to prove his innocence. It’s a messily scripted episode but its status as a kind of Halloween episode for the series gave me a lot to enjoy.

Another example of Star Trek’s wonderful subtlety, as the Enterprise crew encounter a stratified society where the lower class are forced to toil away in underground mines while a wealthy upper class live life to the fullest in a towering city in the clouds. Calling this allegory feels unfair because fewer episodes have put the text in subtext so obviously, but it’s still a fairly good episode that holds some of the series’ most stunning visuals which push the realities of urban life to their science-fiction extreme.

Perhaps no other episode has a more expansive gulf between the strength of its premise and the quality of its episode than Bread and Circuses. A Roman empire that has endured into the modern age is a brilliant premise, an alternate history which more concretely shows humanity’s warfaring nature continuing forwards. But the episode devolves into uninteresting gladiator combat and repetitive conversations about the Prime Directive better seen in other episodes.

One thing that always fascinated me about Star Trek from an outside perspective was its lack of robotic characters. Obviously I knew about Data but outside of him I knew of no machinated characters usually found all over the science-fiction of my youth. Obviously, a large reason why Trek lacks robots is budgetary given its smaller scale television narratives can’t house the kinds of droids found in Star Wars, but Trek does occasionally march into some of this territory. What Little Girls Are Made Of is The Original Series’ major robot episode and is perhaps best remembered for the usage of Ted Cassidy, who plays the massive android Ruk. This episode is an acceptable if forgettable piece of science-fiction, but it’s Cassidy’s stature and presence as Ruk that makes it truly memorable.

After Kirk, Spock, Bones, and Lieutenant Commander Ann Muhall are beamed down to a lifeless planet after a mysterious distress signal draws them to a series of mysterious spheres which release the minds and spirits of a dead alien species. These spirits temporarily take over Kirk’s body and upon his return to his own mind he endeavours to find them a new home. There’s a lot of fun possession performance in this one with these alien beings learning to appreciate what humanity has to offer and while the unwinnable scenario of survival for two species fighting over the same bodies is interesting, the episode never comes together as something truly engaging.

Another case of an interesting premise that just never manages to form into a strong episode. The Enterprise crew encounter Losira, a mysterious woman who appears on the ship and kills members of the crew one by one simply by touching them, creating an effective sense of paranoia as Kirk and the others try to understand what they are dealing with, giving this episode an almost proto-slasher energy. The reveal that Losira is a computer-generated guardian created to protect a doomed colony provides the episode a sadder and more mournful feeling, particularly when the crew discover that the real Losira died alongside everyone else centuries earlier. The episode’s atmosphere is terrific and Losira’s status as a metaphor for the lingering wounds of war makes for an ethereal and mysterious episode.

Is There In Truth No Beauty? gives Star Trek its own Medusa in a sense with Ambassador Kollos, whose very appearance induces madness in those who glimpse him. This Lovecraftian idea of sanity being linked to sight and Kollos’s relationship with Miranda Jones, whose blindness offers a unique relationship, gives the episode plenty of intrigue. Miranda’s character and the inner depth she is imbued with by actress Diana Muldarur are the real star of the show here, and the exploration of her dynamic with Kollos and the unique perspective she can offer gives the episode some unexpected thematic heft.

Star Trek: The Original Series has a fair few episodes featuring characters either inspired by, or connected to, Earth history, partly due to cost-cutting measures but at its best it was used to look to the past to see how humanity has moved into the future. One such episode is Requiem For Methuselah, which sees the Enterprise beam down to the planet Holberg 9-17G in search of a cure for a deadly fever. On this planet, they encounter Flint, who they discover to be an immortal being from Earth’s history who has lived lifetimes as Methuselah, Alexander the Great, and Solomon. Flint’s story is only really hinted at, but the implication of his existence and the contrast between him gives the episode some decent drama, even if it never fully maximises its dramatic potential.

When a group of all powerful interdimensional beings take the Enterprise hostage, our crew are forced to placate them to try and win back their ship. The ways in which each member of the crew does this speaks to them in some delightful ways. Kirk, as usual, leans on his charm and knack for seduction, Bones plants seeds of doubt about the invader’s health, and Spock tries to reason with their leader logically. However the clear highlight of the episode is Montgomery Scott whose great solution is to get one of the intruding aliens good and hammered. James Doohan was a constant highlight of Star Trek: The Original Series for me and I don’t think he was ever more fun than his drunken highjinks in By Any Other Name.

The driving force of Star Trek has always been discovery, strange new worlds, new life, new civilisation, so on and so forth. Humanity’s drive to explore and understand the universe is central to what the franchise is and why it continues to appeal, so the fun of The Changeling is seeing that explorative instinct challenged when Enterprise runs into an old Earth probe which has gained sentience after accumulating knowledge over the centuries. This new mechanical life form and its desire to understand its ultimate purpose offers a fun challenge for Kirk as he and the crew are forced to reckon with the more destructive impulses of humanity’s search for answers.

Star Trek is a terrific vehicle for thought-provoking and challenging science-fiction that can offer a glimpse into a future we can aspire towards, but sometimes, just sometimes it allows itself to be silly and stupid. One of those sometimes is ‘Shore Leave,’ which might as well be the poster child for the ‘filler episode.’ But I don’t believe in filler, especially not when it’s as entertaining as this one. The Enterprise crew beams down to a pleasure planet for a bit of a reprieve from Klingons, alien gods, and unknown cosmic phenomena to boldly go nowhere in particular. From the opening moments when Doctor McCoy spots a white rabbit, this episode’s purpose is clear, to simply be a silly, fun time hanging out with these characters. The various subplots following each character aren’t all made equal but the intentionally deflating and cheap ending brings it all together.

Another early gem of Star Trek: The Original Series’ Season 1, Dagger of the Mind centers on a rehabilitation facility for the criminally insane where Dr. Tristan Adams utilises a new experimental technology to correct his patients’ illnesses. What’s been fascinating about The Original Series is the ways in which Gene Roddenberry’s perfect utopian future is subverted in certain episodes where members or allies of the Federation display more nefarious and dubious morals. Dr. Adams’ barbaric brainwashing and his ambivalence towards his patients’ betterment acts as interesting social commentary on mental health, incarceration, and correctional facilities, and the questions it poses as to whether the galaxy’s worst can truly be helped is compelling material.

A sub-genre of Trek episodes I never tend to enjoy much is the crew beaming down to confront a planet whose culture and society feels backwards and barbaric to them and to ultimately bring them over to the Starfleet (American) way of life. The Prime Directive is established in this episode, the Federation’s moral foundation that posits that advanced civilisations should never impose their technology or principles on less developed planets and cultures. This Directive is all but ignored by Kirk in this episode in an ending which muddies the waters of the episode’s unfocused thematic narrative which gestures at allegory for religion and communism, but never makes a firm commitment to its ideas. Despite all this ‘The Return of the Archons’ is riveting, and with modern eyes feels like a forebear for The Purge series and hivemind narratives like Pluribus. Seeing this society devoid of conflict but lacking all individuality and expression is genuinely creepy, perhaps more-so than any episode of the show.

I think this one is fairly underrated from what I’ve seen about folk’s perspective on it online. The titular Charlie X, a god-like angsty teenager prone to pubescent mood swings and enormous displays of godlike power. In the age of incels and ‘red-pill movements’, centering an episode on a young man grappling with his societal responsibility and raging against a world he doesn’t feel he belongs to is very prescient. The way that Kirk genuinely tries to help Charlie and guide him through it as well is when I really began to fall in love with the character, beneath all the bravado and grit is a very empathetic man, willing to help guide the next generation.

As Season 3 started to wrap up and the show started to wind down, it was clear that the creative team didn’t have much left in the tank, so it was a real joy to have one last great episode before we parted ways. All Our Yesterdays is another time travel episode where Spock and McCoy are sent back into the past of an alien planet while Kirk endeavors to bring them home. Spock and Bones being trapped in the past works beyond just the simple narrative stakes, and acts as the story’s thematic centre, forming a story about the struggle to move forward and the desire to settle for a simpler life.

Can a single performance elevate an entire episode? The Enemy Within makes a damn fine case for that possibility. When Kirk is split into two people after a transporter malfunction (a lot of those in this show), Shatner gets to go absolutely mental, with a performance as his psyche’s aggressive half that is simply a ridiculous amount of fun. There are certainly some interesting ideas in here about how our darker sides are essential to who we are, even if Evil Kirk’s attempted sexual acts take that notion to some uncomfortable places, but the real draw here is seeing Shatner’s bonkers heel turn.

After The Cage failed to muster much excitement at NBC, Gene Roddenberry and Lucille Ball sought a new captain for their second chance, and they found it with Wiliam Shatner. Shatner’s entrance onto the show’s second pilot stands in marked contrast to its predecessor. While The Cage was a slower, more philosophical examination of humanity’s place in a vast, unfeeling cosmos, Where No Man Has Gone Before conjured something more immediate and visceral, with a confrontation more about laser guns and fisticuffs than conversation and compromise. What we’ve come to know as Star Trek came to be defined through these two pillars of intellectualism and pulp entertainment. For this episode’s part, it is a remarkably fun slice of pulp science-fiction with the new Captain Kirk venturing into a corner of the universe which feels genuinely dangerous. Star Trek would certainly improve from here but as a foundation it’s solid enough.

Star Trek’s first foray into time travel, and one which reckons with the fallout of such an action. When the Enterprise is inadvertently flung back towards the 1960s, a fighter pilot stumbles upon the futuristic spacecraft and is beamed aboard. The rest of the episode follows Kirk and the Enterprise crew’s moral dilemma of how to return this pilot to his own time and whether he should be able to or not. Trek would do time travel much better later, but it’s cool to see it utilized here in a way beyond just a simple cost saving measure that actually tries to examine the effects such travel would cause.

The first chapter of the Menagerie two-parter thoroughly impressed me with its worldbuilding, expansion of Spock’s character, and compelling mystery, but sadly its second chapter is a step down. This two-parter was created to finally give air time to The Cage, the series’ failed original pilot which had, until then, gone unseen by the public. While the first part acted as an exciting gateway into showing this old footage, the second half settles into more of a clip show format with Spock giving commentary over footage from the pilot. The ending that it comes to, utilising unused footage from the pilot for a new context is clever and brings it all together but The Menagerie, Part 2 does struggle to stand out as its own episode.

Star Trek does black box theatre. Of course the initial reasoning is entirely budgetary, but the hyper minimalist production values and contained cast of characters gives The Empath a distinctive simplicity that marks it as one of Star Trek: The Original Series’ boldest episodes. This is Star Trek at its basest form: Kirk, Spock, and Bones under extreme pressure trying to solve an unsolvable problem. With everything that Star Trek is stripped back to this basic narrative, the story is able to represent the series philosophical and futurist ethos clearest, expressing that what makes someone humane isn’t intelligence or technological sophistication, but the capacity to recognize another person’s suffering and choose to help them.

Something that sets Star Trek apart from many of its science-fiction contemporaries is the emphasis on each show’s setting as a workplace. Star Wars and Firefly focus on ragtag groups of renegades and rebels, but the casts of Star Trek are responsible, decorated members of a specific organisation. There’s a respect for chain of command and a sense of duty and professionalism that is uniquely Star Trek and no episode emphasises this better than Court Martial. Kirk is court martialed for apparent failure in command which resulted in the death of a member of his crew and the episode takes on the style and format of a courtroom drama to understand what happened and whether Kirk is truly at fault. The episode introduces a lot of excellent worldbuilding with a thorough look at the bureaucratic processes of the Federation. But it’s also one of the best episodes for exploring Kirk as we see firsthand the immense burden of responsibility placed on every action Kirk has to make as a Starfleet captain.

The beginning of Star Trek but not as we know it. The original pilot carries many of the same qualities we know and love about The Original Series as it came to be, but the growing pains evident make it a fun and fascinating glimpse at an alternate future where Kirk never entered the picture. The Cage’s Captain Pike isn’t nearly as compelling as Kirk but the circumstance he finds himself in, trying to escape a human zoo is eerie, pulpy and thought provoking, everything a good Trek episode should be.

One of The Original Series’ more ‘alien’ episodes, with a threat that feels unexplainable and otherworldly as a massive spaceborne organism travels through space draining the energy and life-force of living beings and starships alike. I love when Trek episodes lack a villain and need only a problem for the characters to solve, and few episodes are better at this than The Immunity Syndrome. This organism isn’t malicious or motivated but it is dangerous and the ways in which Kirk, Spock, and McCoy debate how to stop its threat humanely and whether deadly force is justified when a living creature is simply existing naturally. If Star Trek is about seeking out “new life” what happens when that life cannot co-exist with our own? That question drives an underrated gem of an episode that speaks to the science-first, collaborative spirit of solving problems and discovering the impossible that makes Star Trek great.

A murder-mystery in the guise of Shakespeare was about the last thing I expected heading into this episode but I was delighted to find a genuinely compelling story. The Shakespearian acting troupe playing aboard the Enterprise is a perfect match for the old west ‘wagon train’ format of the show, but beyond simple aesthetic pleasures, the episode’s themes on identity and hidden agendas fits perfectly within the premises setup. This is one of those episodes that is barely science-fiction but the quality of the guest stars and the intrigue of their story makes it a delight.

By Season 3, it was clear the show’s budget was well and truly running dry, most evident in the gluttony of episodes locked on the Enterprise or set on Earth-like planets where reused production elements can be excused. Every once and a while though you get an episode that uses its budgetary restraints to its benefit, none finer than Spectre of the Gun, a western episode that zaps our crew to the O.K. Corral to duel Wyatt Earp and Doc Holiday. Beyond just a simple western pastiche the blood red skies and limited set creates an eerie atmosphere as our heroes try to escape a certain doom.

I knew The Next Generation’s first season going into this so it was fairly exciting to see the progenitor of the character that will become Q in The Squire of Gothos. Star Trek has a fair few episodes focusing on beings of immense power toying with Kirk and his crew but none were as thoughtful and entertaining as William Campbell’s Trelane. Trelane’s fascination with Earth’s 18th century, beyond just a cost saving measure of the show’s costumes and sets, functions as a great challenge for Kirk who has to demonstrate the childishness of humanity’s more barbaric years when warfare and militarism steered the direction of civilization. Kirk’s frustration with the immature Trelane gives a lot of comedic value, but his resolute belief in humanity’s growth beyond violence makes me want to believe that such a future is possible.

An episode with the Klingons in Star Trek: The Original Series was always a guarantee for entertainment and few episodes delivered the goods like Day of the Dove. After Chekov instigates conflict with the Klingons in a fit of rage, the barbaric aliens and our Federation heroes are caught in a conflict where aggression, hate, and anger spreads like a disease. Seeing Klingons and a crew of Starfleet officers duel it out on the Enterprise was good, silly, swashbuckling fun but the story’s focus on the cyclical, parasitic nature of anger and violence is well told and reaches one of the most hilarious and heartfelt conclusions of the show.

Of all the episodes of Star Trek this feels perhaps the most modern, which is odd given how much of it focuses on an aged pilot that was never picked up. While it’s true that The Menagerie two-parter was a way for the studio to show their unaired original pilot, the interstitial wraparound and connective tissue is incredibly compelling. Spock going AWOL after a mysterious meeting with Captain Pike this early into the show felt like a unique glimpse into Spock’s character and his ulterior motives that are used later with fuller dramatic material. Spock’s escape and Kirk’s chase of him is really gripping and the ambiguity of his motive and purpose make this a really entertaining two-parter.

One of the greatest joys of this journey into Star Trek has been the realization that the show could be really damn funny. There’s a wonderful sense of wit and a wry workplace comic sensibility at its centre that keeps even the most existential of episodes palatable and relatable. There are a few episodes though where the scales are tipped and comedy comes to the fore and never with more laughs than I’ Mudd. Few episodes turned around for me so rapidly as I’ Mudd, which for me began with frustration at the return of Harry Mudd but ended in uproarious laughter. Kirk’s improvisational gambit in the episode’s final act stands as one of the best moments of the show for me, a completely unexpected turn into absurdist slapstick that really shows how diverse in tone and style this show could be. The moment where Leonard Nimoy slowly pulls out an invisible bomb from under his shirt will stay with me forever.

Personally, part of the fun of Star Trek compared to a lot of other science-fiction is that it acts as a procedural following a crew of hyper-confident individuals, each of whom are the best in the universe at their given job. There’s a professionalism, calm, and matter of factness that makes the characters and their relationships so compelling and memorable. The Naked Time asks the question “What happens if all that professionalism is stripped away?” The absurdity with which the episode interprets that premise makes this a highlight of the early episodes, with Sulu shirtlessly terrorising the crew with a rapier remaining the most iconic. But I think the episode is so compelling because it gets to the root of a common unspoken fear, that we all have to rely on each other for the world to work, that trust in our fellow man’s decency and competency is essential. The Enterprise is a microcosm of civilisation and what happens to civilisation when people’s discipline and social norms fall away? The results are varied and the various ways the crew break down act as interesting peeks into more reserved characters.

A Taste of Armageddon’s Cold War allegory is perhaps a little too far-fetched and absurd to really land, but with time, the episode has taken on different meanings as new technology has emerged. Kirk’s need to help and the planet’s inhabitants’ unwillingness to let him breeds incredibly compelling drama, but this society’s numerical perspective on life where death is dealt out casually and impersonally feels a tad prescient in a world where fully automated warfare creeps ever closer, and with Kirk’s impassioned final speech to strive for peace standing as one of Trek’s greatest moments, A Taste of Armageddon stands tall.

The Tholian Web is one of TOS’s most atmospheric and dramatically compelling episodes, shifting the familiar distress call into something more dangerous and challenging. Kirk is split from the Enterprise and trapped between dimensions, forcing the crew to learn to work without their leader. Kirk and McCoy’s differing approaches to the situation give the episode a lot of drama while the mysterious Web of the episode’s title slowly breaking down reality around them gives the episode a great sense of tension and immediacy.

The introduction of Khan, perhaps Kirk’s greatest adversary and the most iconic villain of Star Trek: The Original Series. Going into this viewing, I knew Khan would reappear down the road but I was really delighted by how immediately compelling the character was in this episode. There aren’t many villains in this show who have the charisma, gravitas, and sheer presence to match Shatner’s Kirk, but Ricardo Montalban goes above and beyond, clearly relishing this opportunity to go big and devour the scenery.

Perhaps the most delightful surprise of the entire series for me was Arena. Anyone who’s even a little versed in popular culture has some awareness of Kirk’s showdown with the lizard-like Gorn. Their scuffle filmed at the iconic Vasquez Rocks with cheap, dated choreography has been made infamous by endless memes and parody. But the actual episode itself is wonderful and genuinely subversive. Kirk chases a Gorn spacecraft across the galaxy after coming across a Federation colony they had apparently wiped out. The episode then follows a physical battle between the two species, left to fend for themselves on a barren wasteland. Kirk’s struggle to survive, his adaptation to his surroundings, and his utilisation of his environment make for a really thrilling episode, but the eventual conclusion to the story stands among my favourite moments of the series. A moment of mercy and forgiveness, and for the time, a fairly radical critique of colonialism that stands as one of the clearest examples of Trek’s uniquely utopian perspective.

While Kirk and Spock are the undisputed core duo at the centre of Star Trek, the pairing of Mister Spock and Doctor McCoy is perhaps even more compelling. Bones’ cynicism, southern wit, and fiery temperament is a perfect counter to Spock’s clinical, restrained, and objective approach to every scenario is a breeding ground for conflict. The Galilelo Seven acts as an early sparring match between the two when Spock is left in command of an away team stranded and separated from Enterprise. The two characters’ differing approaches to leadership and survival is incredibly compelling and the hard fought battle to go home lays the groundwork for the continuing development of their growing respect for the other.

I don’t think you’d be able to count the amount of romantic subplots Kirk had over the course of the series and yet his pointy eared co-star deserved some love as well and it eventually came with The Enterprise Incident. Illegally entering Romulan space to sabotage a prototype cloaking device, the age-old plan of Kirk seducing while Spock slinks around is inverted in a terribly fun episode. Kirk faking his death to cosplay as a Romulan is a wacky surprise but the touching and questionably false relationship between Spock and Joanne Linville’s Romulan commander gets to the heart of the Vulcan better than almost any episode.

I’ve always been a big fan of politics in my sci-fi. There is no greater way to expand and deepen a fictional setting than to delve into the messiness of its institutions and the tensions within its society, seen expertly in Journey to Babel, which, beyond introducing Spock’s parents, also introduces a host of new alien species and cultures. Star Trek: The Original Series rarely felt so expansive and the various tensions, uneasy alliances, and generational anger between the various cultures and species fills out the world as something more believable and grounded than the episodic format usually allowed. Beyond the political intrigue and murder mystery, Journey to Babel also gives us some of the best character work for Spock as we get to see firsthand the struggle between his human and vulcan sides.

By this point in the series, alternate Earth episodes were starting to become tedious, but thankfully A Piece of the Action rose above all of them as the easy highlight of this format. Kirk, Bones, and Spock beam down to a planet which has modelled itself on prohibition era Chicago gangsters, which stands amongst the most ludicrous premises in all of Trek. The setup leads to endless amounts of hilariously absurd setups, with Shatner especially clearly relishing the opportunity to get incredibly silly, waltzing around with a broad accent, pin stripe suits, and tommy guns. It’s an episode that knows exactly how silly it is and embraces it, and is the prime example of the kind of tonal variety this show offered at its best.

A mysterious alien monster terrorizing a human colony is an old staple of pulpy science-fiction storytelling, usually a proven story template for episodic television that allows the audience to get the thrills and excitement they expect, but Star Trek was never a show content to do what was expected. The Devil in the Dark stands as a brilliantly subversive deconstruction of this narrative archetype, focusing on Kirk and Spock’s desire to understand and help the supposed monster terrorising humanity. Spock’s pained mind meld with the Horta creature is a key moment of The Original Series, and for Spock as a character. For someone so dedicated to logic and reason to be so empathetic that he feels the literal pain of the oppressed, especially after initially attempting to kill the creature, demonstrates that logic and compassion cannot be separated. The broader environmental and colonial themes of the ignorant humans inadvertently killing the creature’s kin from unsafe mining and their subsequent hatred of the avenging creature position humanity’s greatest failing as its willingness to treat the unfamiliar as something to be feared and destroyed. The episode stands out as incredibly progressive and forward thinking for 60s science-fiction. Star Trek at its finest.

The introduction of Klingons to the world of Star Trek and what an introduction it is. While initially caught off guard by the lack of headridges and the troubling usage of makeup, the Klingons I have come to understand from popular culture are really here from the jump. Their status as a warfaring species of warriors where the dominant culture holds combat and honour above all else is used expertly here to demonstrate humanity’s overcoming of a more violent past and while the Cold War allegory here is simple it does a lot to build out the universe and lays seeds for the rest of the franchise to grow.

The Ultimate Computer’s central dilemma of technological agency and the line between progress and the loss of human control surely felt like science fiction in 1968 but today becomes more and more relevant by the day. When Dr. Richard Daystrom beams aboard the Enterprise with orders to test the capability of a new M-5 computer system, immediate questions are raised about the dangers of automation and lack of human oversight. The story of the A.I software gaining sentience and turning on its human creators is tried and true and fairly rote material by now, which gave the more mature and thoughtful turn into difficult questions raised by The Ultimate Computer a lot more weight. Because M-5 isn’t just a villainous rogue A.I, his methods were successful, the Enterprise proved to be more efficient and delivered impressive results even if the machine’s lack of human understanding made it dangerous. In an era where our own version of A.I is creeping into more and more workforces in the name of productivity and efficiency, to have an episode focus on the dangers of technological progress without boundaries, and the essential human element to decision-making, is remarkably prescient.

The first episode of The Original Series to well and truly blow me away. The Corbomite Maneuver is a rip-roaring piece of sci-fi entertainment that to me stands as the best showcase of Kirk’s character and command in the series. The overbearing, unknowable alien craft gives the episode a constant sense of danger as our crew desperately try to escape a situation they can barely comprehend. Kirk’s decision to bluff stands as an early example of his improvisational ability that gives him victory in many of The Original Series’ stories, but the reveal that this immensely powerful alien was also bluffing renders the episode as an insightful examination of fear in first contact encounters. An episode that begins with apprehension and confrontation ends with new friendship and discovery. It’s the first time that I felt I saw what Star Trek could truly be, not just as a television show but as an optimistic look forward to a future where the unknown is something to be understood and not feared.

One of Star Trek: The Original Series’ most straightforwardly thrilling episodes. After stumbling upon a massive un-identified alien vessel carving a destructive path through the universe, Enterprise endeavors to halt its path and understand its origin and purpose. One of the real draws of this episode is the appearance of Commodore Decker, the commanding officer of another Federation starship caught in its path. Beyond the fun of finally seeing another Starfleet officer, William Windom gives one of the show’s finest guest performances which runs the gamut of mania, sympathy, and everything in between. His utter terror at the mysterious Doomsday Machine and his fixation on destroying it alongside the mystery and scale of the machine itself gives the episode an air of cosmic horror which helps to convey the immense danger and unknowability of the universe more than any other episode.

One of the most delightful surprises of the show for me was this wonderful little comedy that manages to touch on some surprisingly astute and well observed Cold War commentary. While most of the episodes of The Original Series that try to touch on the Cold War do so with allegories for proxy wars or nuclear weaponry, the struggle over resources in The Trouble With Tribbles stands out as unique, insightful, and incredibly novel. The Enterprise crew trying and failing to play nice with the Klingons in a neutral space station gives ample drama and plenty of laughs but the growing background narrative of Tribbles overrunning everything makes this one of the best of the series.

Star Trek is generally plot driven with episodes centering around vaccines, dying stars, and galactic proxy wars, so Amok Time’s character-focused narrative was a riveting break from formula. Spock undergoes what is known as the Pon Farr, a condition affecting Vulcans where they must mate every few years or die. To resolve this, Enterprise travels to Vulcan where Kirk is embroiled in a passionate fight for the soul and life of his first officer. It’s a thrilling episode focused on character and not on story, with a terrific central conceit that proves to Spock and the crew how much they mean to the other. Balance that out with a major expansion of the Star Trek setting with a deepened Vulcan culture and society and you’ve got one of the best pieces of Trek there has ever been.

I’ve always been a sucker for evil alternate narratives where heroes confront their warped mirror image, be that DC’s Earth 3, Coraline, or the modern Wolfenstein games and perhaps no piece of fiction has been so foundational for this trope than Mirror, Mirror. When a transporter beam malfunction swaps Kirk, Uhura, Scotty, and Bones with their counterparts from another reality where Earth grew into a conquering empire instead of an explorative Federation, the crew are forced to sleuth around and find a way back home. Beyond the immediate joy of seeing our cast ham it up with real malice and venom there’s something truly thought provoking that comes into view at the episode’s conclusion. Kirk’s plea to this mirror version of Spock took this already great episode to incredible highs, and suggests that maybe much of who we are comes from within us and not from the world that we were born into.

Perhaps the most lauded and acclaimed episode of The Original Series, The City on the Edge of Forever stands as a pillar of science-fiction. Initially penned by Harlan Ellison, the episode had a long journey to the screen with endless disputes and rewrites that ultimately formed it into a true masterpiece. To me, The City on the Edge of Forever stands as one of Star Trek’s most emotionally resonant achievements, distilling the series’ optimism and humanity into a tragic story about love, sacrifice, and the inevitability of history. The episode’s displacement of Kirk and Spock into Depression-era America creates an unusual contrast between Star Trek’s optimistic future and a world defined by poverty, war, and uncertainty, while Edith Keeler’s warmth and idealism make her eventual fate all the more devastating. Its time-travel premise is ultimately less interested in the mechanics of history than in the painful knowledge that some events cannot be changed, even when changing them would mean saving the person you love. The result is a beautifully constructed and deeply melancholy hour of television that demonstrates Star Trek at its most human, hopeful in its belief in a better future, yet willing to confront the terrible sacrifices required to reach it.

Balance of Terror, to me, is the apex of Star Trek: The Original Series and represents all that made it compelling and timeless. The episode’s introduction to the mysterious Romulan Empire creates space for exploration of nuclear deterrence, Cold War paranoia, and generational prejudice, but the commitment to developing the Romulan adversaries as real living people gives the episode a sadder and more introspective atmosphere that forewarns a doomed ending we know cannot be avoided. The episode is a tight, perfectly scripted, and wonderfully directed hour of television that shifts Star Trek’s spacebound future into something resembling the familiar naval warfare of the modern age, juxtaposing an aspiration for peace with the realities of conflict and command. Yet, beneath its tense tactical drama, is something far more melancholy, a story in which victory feels indistinguishable from loss, and where Kirk’s enemy ultimately becomes someone worthy of his respect and sympathy. In making war feel both necessary and profoundly tragic, Balance of Terror captures the uneasy humanism at the heart of Star Trek better than almost any other episode.