I meant to post this exactly on September 8th, but it got away from me. But I still want to share this because 50 years ago, NBC aired the very first episode of Star Trek. Both Sam and I are huge Star Trek fans — in fact, here’s a photo of us visiting Captain Kirk’s future birthplace in Riverside, Iowa earlier this year!

I could go on and on about why I love Star Trek and what it means to me — but ask me in person and when you’ve got hours to spare because I will talk your ear off and maybe also involuntarily cry a bit. Something about Star Trek drives past my crunchy exterior into the warm, squishy caramel of my soul. So in celebration of this anniversary and because I feel like it, here are my 10 favorite episodes of Star Trek: TOS, all of which you can stream right now from Netflix.

10. The Doomsday Machine (season 2, episode 6)

There are a few “officials who pull rank and put the Enterprise in jeopardy” episodes out there, but this storyline with Commodore Decker is by far one of the most intense. The Enterprise goes to answer a distress call from the USS Constellation, only to find it severely damaged and the entire crew missing, aside from Decker, the Constellation’s captain. It turns out Decker had tried to save his crew from a giant attacking machine by beaming them down to a planet, only to witness that same machine devour the planet, taking his crew with it. Obsessed with his need to destroy the machine that destroyed his ship and his crew, Decker perilously takes command of the Enterprise while Kirk is stranded on the barely functional Constellation. Scotty also has a big part in this one, and I feel like every episode could have used more Chief Engineer Montgomery Scott.

9. The Immunity Syndrome (season 2, episode 18)

Kirk and Spock may be the duo of all duos, but I firmly believe that it is Bones and Spock who have the best banter. The good doctor and the Vulcan constantly butt heads, and even when they’re legitimately arguing about who gets to risk his life to probe a giant space amoeba, it’s undeniably entertaining. Maybe because you can just sense that underneath all that bickering is a real bond of brothers, even if neither would ever admit it. Like The Doomsday Machine, this episode is tense and involves a literal giant threat, but I love it all the same for the Spock and McCoy moments alone.

8. The Balance of Terror (season 1, episode 14)

This episode introduces the Romulans, even though I think they were mentioned before as vague enemies of the Federation. In any case, there was a massive war between the Romulans and the Federation a century ago, which only ended with a tenuous peace treaty involving the establishment of a Neutral Zone that neither are to cross. And more importantly, because of how long ago this war took place (and I guess because spaceships don’t exactly have giant bay windows), neither side actually knows what the other looks like — until now. And surprise! the Romulans sure look a lot like Vulcans, something which a bitter crewmember brings up when they’re in the heat of battle.

Star Trek is great at doing storylines that showcase very real human problems and shortcomings, even when it’s set 200+ years in the future and in a completely foreign environment. The crewmember’s swipes at Spock for his resemblence to the Romulans — keeping in mind that Spock is not a Romulan and more importantly, has been an integral part of the Enterprise crew for a very long time up to this point — is an all too familiar reminder of how racism, even among allies, can flare up at the slightest provocation.

7. Journey to Babel (season 2, episode 10)

Spock’s parents! We get to meet Spock’s parents! A fun thing you’ll notice is that the same actor who played the Romulan captain in Balance of Terror also plays Spock’s dad, Sarek. Make of that what you will, though it’s not the first time the same actor has been employed to play different characters (another is the actor who played General Trelane in The Squire of Gothos and then a Klingon in The Trouble with Tribbles, but that’s neither here nor there). In this episode, there’s a space UN meeting of sorts on the Enterprise to discuss the admission (or non-admission) of a specific star system into the Federation. Things are already volatile because all the ambassadors on board have strong opinions on the matter (lots of political feuding in this one), but then things get kicked up a notch with murder and sabotage and Sarek’s sudden heart attack. Plus, the relationship between Sarek and Amanda (Spock’s human mom) is incredibly sweet.

6. Mirror, Mirror (season 2, episode 4)

Ah, the “evil twin in an alternate universe” episode. Which makes me wonder, are the Romulans the peaceful species in this mirror universe? That isn’t discussed, but what we do know is that in the Evil Reality, the Enterprise crew kills and tortures one another for promotion. Yikes. Evil Sulu even has a wicked long scar on his face, no doubt from some previous fracas. A freak ion storm and transporter accident sends Kirk, Uhura, Bones, and Scotty to the Evil Enterprise, where they have to pretend to be their evil counterparts to evade detection, all the while trying to figure out how to get themselves back to the Good Enterprise. Plus, Uhura has a crop top that shows off some killer abs, and Kirk has a kicky sparkly sash. Evil Spock even has an evil beard. I mean, the Evil Enterprise may be, well, evil, but they sure looked awesome while doing their evil things.

5. The City on the Edge of Forever (season 1, episode 28)

This one will break your heart on behalf of Captain Kirk. The man has traveled across galaxies and met and kissed many a beautiful space woman, but the first time he truly falls in love, it’s with a woman who is destined to die. The episode kicks off with Dr. McCoy accidentally shooting himself with a hypo full of something that makes him go absolutely fucking bananas. After a series of accidents, he ends up jumping back into 1930s-era Earth and doing something that alters history so severely that Starfleet no longer even exists. The only choice Kirk and Spock have is to go after him and stop him from doing whatever it is that changed everything. Once in the past, Kirk meets Edith Keeler, a forward-thinking, self-made woman who runs the 21st Street Mission (and fun fact: she’s played a pre-Dynasty Joan Collins!). But while he’s there with Spock awaiting the arrival of Dr. McCoy, they learn that the one thing McCoy likely did was prevent Edith Keeler’s untimely death. In other words, to restore the future to what it should be, Kirk must let Edith die. It’s heart-wrenching, and one of the only episodes to end on a pretty downbeat note. I mean, the last line is Kirk angrily muttering “Let’s get the hell out of here.”

4. A Piece of the Action (season 2, episode 17)

I have to admit that I seem to like every episode where Kirk and Spock dress up in “old Earth” clothes — even the one where they dress up as Nazis (not on this list, but yes, Nazis). And this episode may or may not be responsible for one of the more bizarre and specific sexual fantasies I may or may not have. Ahem. The crew finds themselves on a planet that has modeled itself after 1920s Chicago gangs for flimsy reasons that are not important, only that it gives Kirk and Spock the excuse to wear sharp suits and carry Tommy guns. It’s one of the sillier episodes, with Kirk affecting a “wise guy, eh???” accent and Spock learning that his captain can’t drive a car worth a damn.

3. The Corbomite Maneuver (season 1, episode 10)

The Enterprise crew encounters some weird shit in space, and this time it’s a Windows screensaver– er, “space buoy.” Captain Kirk shows off just how clever he can be to avoid getting his ship blown to smithereens by a hostile alien. The Enterprise is outmatched, and the alien aggressor gives the crew an ominous countdown to their own destruction. It’s interesting to watch one of the newer bridge crewmembers have a complete meltdown in the face of helplessness, and it shows just why the usual bridge team is so impressive: they’re worried, of course, but they keep their shit together, even when there doesn’t appear to be a solution. The “villain” twist at the end just underscores how things are sometimes not at all what they seem.

2. The Devil in the Dark (season 1, episode 25)

One of my favorite McCoy “I’m a doctor, not a ______!” exclamations is in this episode: “I’m a doctor, not a bricklayer!” An important mining colony has found itself suddenly besieged by a mysterious monster that is melting the miners one by one. Yes, melting. Or burning to a crisp. Or both simultaneously. Look, they’re dying, okay? And as if that weren’t bad enough, it also stole a piece of critical life support equipment, making it only a matter of time before things get much, much worse. The Enterprise is summoned to find out what’s going on, and Kirk and Spock soon encounter the monster (called a Horta) and find that it has a very good reason for doing what it’s doing. I just plain loved the story of this one, and the way Spock’s stance jumps immediately from “we should trap the creature” to “we should kill the creature” the moment Captain Kirk is the one who is trapped with the Horta.

Side note: I swear that I read somewhere once that in the digitally remastered version of this episode, you see some of the miners playing with a baby Horta in the background of one of the scenes, but despite looking and looking, I’ve never been able to see this. And that is immensely disappointing. I want to see a baby Horta, damn it.

1. The Trouble with Tribbles (season 2, episode 15)

I do think you have to have to be familiar and fond of the crew to really appreciate the absolute perfection of this one. It is hands down the funniest TOS episode, and you have never seen Captain Kirk sass someone so relentlessly until you’ve watched this. Sure there’s an overly long bar brawl sequence in the middle, but it’s worth it just to see Scotty’s indignation when he explains to Kirk that he threw the first punch because some punk ass Klingon called the Enterprise a garbage scow. It also doesn’t hurt that the titular tribbles are so damn cute, despite being just balls of fur that end up everywhere. I mean, I can’t even choose just one screenshot to share, so here is one more:

Happy Star Trekking!