What the cast and crew of Star Trek: Deep Space Nine achieved over 176 episodes was astonishing. Imagine, for a moment, the second spin-off of any other program not only running for seven seasons, but doing so while maintaining an admirably high level of quality and depth. While confronting and exploring the nature of military occupation, spirituality, and interracial marriage, as well as the correct way to cook gumbo.

Created by Rick Berman and Michael Piller, the show carried the shared ethos with other stories in the Star Trek universe of honor and camaraderie, but it had a structural advantage that allowed it to probe its characters in a completely different way. By keeping them stationary, by not having them encounter a new life form every week, Captain Sisko (Avery Brooks) and his blended crew were more often forced to face each other in close quarters, enduring and reveling in each other’s vices and virtues.

These 12 episodes are the best examples of the height Deep Space Nine was capable of reaching.

12. “Inquisition” (Season six, episode 18)

An Inception-esque tale about subterfuge and loyalty, this episode sees Dr. Bashir (Alexander Siddig) as the prime suspect of an internal affairs inquiry conducted by Luther Sloan (William Sadler) regarding a potential Dominion spy aboard the station. It becomes clear that Sloan suspects Bashir when Bashir’s selfless actions are twisted into sinister intent, but when Captain Sisko and the rest of the crew start to believe Bashir is a traitor, the reality of what’s going on gets murky.

It’s impressive to see how far the boyish, genetically enhanced bro of the series evolved by the sixth season, and “Inquisition” does great work reframing our understanding of his past actions, including his search for a cure for the enemy Jem’Hadar’s addiction to Ketracel White. It’s a noirish blend of the Bashir we know from episodes like “The Quickening,” where he stays behind on a planet in order to find an antidote for a plague, and “Our Man Bashir,” where he lives out his fantasy of being James Bond with real-life stakes in the balance. Tight as a drum, the episode relies on paranoia and Bashir’s longheld outsider status while launching a diabolical enemy operating inside the Federation itself.

11. “In The Pale Moonlight” (Season six, episode 19)

With the war against the Dominion teetering out of the Federation’s control, Captain Sisko enlists the help of former Cardassian spy/current style icon Garak (Andrew Robinson) to bring the Romulans to their side by faking a recording of Dominion representatives plotting to attack Romulan bases. The decision to rely on subterfuge becomes a scummy snowball that Captain Sisko can’t extricate himself from before the avalanche falls.

An episode about dancing with the devil, it’s a heart-crushing look at the lengths an honorable man will go to debase himself so that a war might be saved. It’s told in flashback with Captain Sisko narrating a captain’s log, staring directly into our eyes. That decision to break the fourth wall demands that we judge a character we’ve loved and known to be beyond reproach, further complicating a complex leader. The episode also makes a sharp companion to season five’s “By Inferno’s Light,” where we learn more about Garak’s haunting past.

10. “Children of Time” (Season five, episode 22)

One of the bigthink, timey-wimey stories, this episode sees the crew of the USS Defiant stranded on a planet filled with their own descendants, leaving Captain Sisko, Jadzia (Terry Farrell), O’Brien (Colm Meaney), Dr. Bashir, Worf (Michael Dorn), Kira (Nana Visitor), and an aged Odo (Rene Auberjonois) with the insane ethical quandary of whether to effectively kill entire generations of people by escaping or to accept their profoundly life-altering fate. That fate also includes watching Kira, who was injured in the crash, die in two weeks because Bashir lacks the equipment needed to save her.

“Children of Time” illustrates a fun twist to the Star Trek tradition by making the “new life and new civilization” they encounter be their great-great-grandkids. They learn who these people are, admire them, and come to a decision that takes an iron stomach to fathom. But beside the macro question of if you could commit genocide by altering history is the micro question of whether you could let someone you love dearly die when you know what would save them. In that latter sense, it’s a fantastic episode for exploring Odo’s love and dedication to Kira.

9. “Necessary Evil” (Season two, episode eight)

On that subject, there’s probably no relationship more tangled in television history than Odo and Kira, and this episode helps show why. In it, a secret box, a list of Bajoran names, and an attempt on Quark’s (Armin Shimmerman) life force Odo to confront a cold case he tried to solve while working under duress for the Cardassian’s during the Bajoran Occupation. The past and the present collide while Kira’s deadly actions as either a terrorist or freedom fighter (depending on what side of the fence you’re on) come into blunt repose.

Stern-yet-lovable Odo ends the episode unsure of whether he’ll be able to trust Kira ever again, but his own past actions aren’t all that admirable either, proving that name tags don’t simply fall off when the war is over. At the same time, our identities need not be cemented if those around us are capable of grace and mercy.

8. “Soldiers of the Empire” (Season five, episode 21)

Worf and Jadzia briefly join the crew of the Rotarran, under the command of General Martok (J.G. Hertzler), an old salt Klingon who’s recently escaped from a Dominion prison camp. But their mission to recover a missing Klingon ship starts off poorly because the Rotarran’s crew is deflated by the strength of the Dominion’s Jem’Hadar warriors and a series of losing battles. Martok goes a little Colonel Kurtz-y on everyone, and Jadzia has to challenge Worf to challenge Martok for command before he gets them all killed with his cowardice.

Farrell is an exquisite badass as the ancient, wise Jadzia Dax, but the episode is foremost a completed circle for Worf that builds on his personal history as the member of a disgraced and discarded Klingon House. It’s also a testament to the show’s ability to mold a minor recurring character like Martok into a vital presence, inter-personally embedded into the life of one of the show’s best.

7. “Past Tense” (Season three, episodes 11/12)

Captain Sisko, Dax, and Bashir are thrown all the way back in time to 2024 where a grotesque division between the wealthy and the poor has led to barbaric Sanctuary Districts that were supposed to solve homelessness by forgetting about the homeless. They arrive shortly before the historic Bell Riots, a turning point in human history marked by the self-sacrifice of a demonstration leader named Gabriel Bell. When Bell dies helping Sisko and Bashir, Sisko assumes his identity (as well as the responsibility of dying as a martyr), and the timeline alters life for O’Brien, Odo, and Kira back aboard Deep Space Nine.

A stirring work of socially-aware science fiction, it’s a rare chance for Deep Space Nine to comment directly to something plaguing our own time instead of using metaphors or hinting at problems obliquely. It’s also a vein-freezingly tense hostage drama with the stakes cranked all the way to 11. While Dax worriedly engages with 2024’s economic instability intellectually, and Bashir and Sisko tightrope walk over history’s grave with loaded shotguns, the crew back on Deep Space Nine attempt to thread a near-impossible needle to get their friends back.

6. “Trials and Tribble-ations” (Season five, episode six)

You probably can’t tell by this list, but Deep Space Nine had a great sense of humor. The heady doom and gloom of diplomacy and war were met in equal measure by friendly gags and silly excursions. This episode is the show at its most nostalgic and most entertaining.

A hitchhiker causes the Defiant to go off course by 200 light years and 100 years, placing them in the path of the USS Enterprise under the command of James T. Kirk, who’s about to be on the wrong end of an assassination attempt. The Deep Space Nine crew was digitally inserted into the iconic “The Trouble With Tribbles” episode (with classic footage from “Mirror, Mirror” also used), allowing Sisko and the gang to solve their problem while dancing through the background of a fan favorite. The production design and camera crew ensured the authenticity needed to deliver on the fluffy, ’60s-riffing gag.

5. “Homefront”/”Paradise Lost” (Season four, episodes 10/11)

The primal fear of going against an enemy like The Founders is that they, as Changelings, could be anyone or anything, and this two-part mines that fear as a political danger when the Dominion-leading foes are the prime suspects in a heinous attack on Earth. Sisko, his son Jake (Cirroc Lofton), and Odo travel to investigate, splitting their time between San Francisco (where Nog, played by Aron Eisenberg, is stationed) and Sisko’s father Joseph’s (Brock Peters) creole restaurant in New Orleans.

While the investigation and security protocols make the plot spin, Sisko’s relationship with his son and his father are in the forefront, digging a thousand miles deep into these familial figures at odds with each other. It doesn’t get better than Angelica Jade Bastien’s piece at Vulture proclaiming that Deep Space Nine is “TV’s most revolutionary depiction of black fatherhood,” noting these episodes among many and remarking, “When I see three generations of the Sisko family onscreen in episodes like the season-four two-parter ‘Homefront’ and ‘Paradise Lost,’ a tinge of wonder rises in me. How often have we seen a black family given such importance, depth, and cultural weight on a television show such as this?” These episodes are stellar examples of how the show boldly went where sci-fi TV needed to go.

4. “The Visitor” (Season four, episode two)

Speaking of which, this episode is just absurd in its scope and emotional impact, charting a course through Jake Sisko (with Tony Todd portraying the older, hermit version) and exploring how his father’s impact left a crater in his heart. It’s a Gordian time travel mini-epic that features an accident during the Bajoran wormhole inversion that sends Captain Sisko into a subspace dimension, frozen in time, popping up as a kind of ghost throughout various points of Jake’s life.

Jake becomes obsessed with saving his father, abandoning his writing career and his marriage, and offering us a vision of 50 years into the future where Nog is a captain. The ending is an advertisement for Kleenex that’s also a tidy sci-fi loop brightened by a father and son both equally willing to sacrifice themselves for the other.

3. “It’s Only a Paper Moon” (Season seven, episode 10)

Who thought Nog would become such an important figure? The show was on air long enough to see him go from annoying bar back for his Uncle Quark to a wannabe cadet rebelling against Ferangi culture to  war veteran suffering with PTSD.

In this poignant, sympathetic episode about finding your way out of the wilderness, Nog fights flashbacks and phantom leg pain, He loses himself inside the holosuite where Vic Fontaine (James Darren) croons torch songs and talks the cane-sporting Nog through a deep depression, eventually leading him to the starting line of overcoming his condition. The power of the story is even more incredible when you consider that its shouldered by two actors who weren’t series regulars.

2. “Duet” (Season one, episode 19)

Just before the end of the first season, Deep Space Nine planted a flag to announce its true potential to wrestle with impossible human questions and emotions. The heart of “Duet” is a series of conversations between Kira and Aamin Marritza (Harris Yulin), a Cardassian she’s interrogating as a potential war criminal. His rare illness tips her off to his presence at an infamous labor camp, but he’s not who he initially appears to be, and Yulin’s portrayal is just this side of mustache-twirling to fully highlight how desperate his plan is.

What’s most remarkable about the episode is its confidence, both in handling a slew of sensitive topics (post-war justice, frailty, compassion) and in plotting a compelling tale mirroring the Nuremberg Trials. Visitor is simply outstanding as Kira as she drifts through confusion and outrage toward an impossible goodwill, delivering a character defined as much by her newfound warmth as her bone-deep rage.

1. “Far Beyond the Stars” (Season six, episode 13)

This episode is a mixture of every wonder Deep Space Nine has to offer. Following the death of a friend in battle, Captain Sisko enters an escapist fantasy where he’s Benny Russell, a trailblazing African-American sci-fi writer in 1950s New York City. His mid-century dream is populated by his crew—Odo is his editor, and Quark, O’Brien, Kira, and Bashir are fellow writers. Cassidy (Penny Johnson Jerald) is Russell’s waitress girlfriend, Worf is a popular baseball player who flirts with her, and other minor characters are sprinkled throughout as “Benny Russell” writes a story called “Deep Space Nine” which features a black space captain.

Directed by Brooks, “Far Beyond the Stars” is not only a nod to science fiction history and about as meta as it gets (forcing us to question if Benny is Sisko’s delusion or the other way around), it’s also a dynamite opportunity for the ensemble to reflect each individual actor’s talent to shine brighter. That we get to see everyone play together gives this episode a leg up, and the core story is phenomenal—a trenchant excoriation of racial exclusion, a deepening of the show’s main character, a fun jaunt in period clothing, a curious thrill in seeing actors like Dorn and Eisenberg out of their makeup, a tragedy of creativity’s inability to assert itself on the real world, and a hopeful beacon present in the very show that we know fulfills Benny’s dream of progress.

What are your essential Deep Space Nine episodes?

Images: CBS Television

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