Star Trek: Deep Space Nine’s Must-Watch Episodes

Last week, we gave you a guide to the highs of Star Trek at its apex of idealistic sci-fi in The Next Generation. But even the brightest light must cast a shadow, and no Star Trek show has embraced or understood that like arguably its headiest, dramatic entry in the franchise: Deep Space Nine. Want to dive into Trek’s dark heart? We’re here to help.

As part of our ongoing efforts to give you things to distract yourself in the moment of history in which we live, io9 is going to be offering up weekly guides to the very best that each Star Trek show has to offer, from the original all the way up to Star Trek: Discovery. So if you’re about to follow our advice and help yourself to all the Star Trek, here are at least some highlights you can look forward to as you boldly go absolutely nowhere outside.

Season 1

Emissary (Episodes 1 and 2)—Commander Benjamin Sisko, haunted by the traumas of surviving the infamous Battle of Wolf 359, is given a new position: command the formerly Cardassian-owned station Deep Space Nine, as the recently liberated planet Bajor transitions out of the Cardassian Empire’s occupation and the Federation attempts to woo the Bajorans into membership. Oh, and meet some Gods, apparently.

Q-Less (Episode 7)—John DeLancie returns as Q for the first and last time in DS9, as you learn just how different Commander Sisko really is from Jean-Luc Picard.

Battle Lines (Episode 13)—A trip through the recently opened wormhole to the Gamma Quadrant changes Kira Nerys’ life when the Bajoran spiritual leader, Kai Opaka, is mortally wounded.

Progress (Episode 15)—Kira faces her new role as a liaison for the Bajoran government when she’s tasked with moving farmers from their land.

Duet (Episode 19)—The past of the Cardassian Occupation comes back to haunt Kira when a Cardassian claiming to be a horrifying war criminal arrives on DS9. A rare sample in this first season of the gutwrenching highs DS9 has to offer.

In the Hands of the Prophet (Episode 20)—A multi-species school set up by Chief Engineer Miles O’Brien’s wife, Keiko, creates a religious debate that the sinister Vedek Winn plans to capitalize upon.

Season 2

Homecoming, The Circle, and The Siege (Episodes 1-3)—The return of an iconic Bajoran war hero to prominence creates a dire scenario for Starfleet, when a military coup on Bajor sees the Federation and Bajorans clash over control of DS9.

Rules of Acquisition (Episode 7)—The Ferengi’s Grand Nagus tasks bar proprietor Quark with an economic mission to the Gamma Quadrant, where he learns of a mysterious faction called the Dominion. Bet they’ll never show up again!

Necessary Evil (Episode 8)—Security Constable Odo reflects on how he got into law enforcement at the height of the Cardassian occupation.

Sanctuary (Episode 10)—Kira finds herself in a tough spot (again) when she has to deal with alien refugees fleeing the Gamma Quadrant and the Dominion’s wrath.

Blood Oath (Episode 19)—Dax’s past lives as a Joined Trill come back to give her a bit of a romp with some very old friends: Kor, Kang, and Koloth the Klingons, who were actually in the original Star Trek, albeit with significantly better makeup this time.

The Maquis, Parts 1 and 2 (Episodes 20 and 21)—It’s easy to be a saint in paradise. Sisko has to team up with Cardassian Gul Dukat to try and quell a guerilla group of colonists fighting back against Cardassian control.

The Wire (Episode 22)—Perfectly Innocent and Not At All Mysterious Cardassian tailor, Garak, has some Perfectly Innocent and Not At All Mysterious headaches. Everything’s fine.

Crossover (Episode 23)—Return to the Mirror Universe for the first time since the original Trek, only to find that things have gotten...much more interesting there.

The Collaborator (Episode 24)—The election of Bajor’s next Kai boils down to a contest between scheming Vedek Winn and beiger-than-wallpaper-paste Vedek Bareil.

The Jem’Hadar (Episode 26)—Starfleet makes a deadly encounter with the footsoldiers of the Dominion: the titular Jem’Hadar.

Season 3

The Search, Parts 1 and 2 (Episodes 1 and 2)—Deep Space Nine gets a tough little ship, the Defiant, and Odo discovers a shocking secret about his species: they’re the founders of the Dominion!

The House of Quark (Episode 3)—Lighten up a bit after all that with a fun Ferengi romp, when Quark accidentally embroils himself in a Klingon blood feud.

Second Skin (Episode 5)—Kira wakes up to a horrifying reality: is she really a deep-undercover Cardassian sleeper agent?

The Abandoned (Episode 6)—Odo goes through Some Feelings when he is forced to adopt a young Jem’Hadar.

Defiant (Episode 9)—As Sisko and Dukat are forced to cooperate against a Maquis attack, Commander William T. Riker arrives on Deep Space Nine. Or does he?

Past Tense, Parts 1 and 2 (Episodes 11 and 12)—Sisko, Dax, and Dr. Bashir find themselves flung back to a dark part of Earth’s 21st-century history: the Bell Riots of 2024.

Life Support (Episode 13)—Vedek Bareil is wracked with a life-threatening illness, but Kai Winn needs him alive to help negotiate a peace treaty, putting Kira in one of those hard places she finds herself in so often.

Heart of Stone (Episode 14)—When trapped in a cave with Kira as she’s slowly encased in stone, Odo begins to open up to her. Meanwhile, Rom’s frequently wayward son Nog decides he wants to enroll in Starfleet Academy.

Improbable Cause and The Die is Cast (Episodes 20 and 21)—The bombing of Garak’s tailor shop embroils him and Odo in a shadow war between the Cardassian and Romulan Secret Polices...and a much larger conflict beyond even that.

Explorers (Episode 22)—A literal ship-building project leads to some emotional, important father-son time between Sisko and his son, Jake. Important facial hair appears.

Family Business (Episode 23)—Quark returns to Ferenginar to help his mother deal with the Ferengi Commerce Authority (and challenge the patriarchy!).

Shakaar (Episode 24)—Not satisfied with being its spiritual leader, Winn plans to become Bajor’s political one—putting herself in an electoral contest with the leader of Kira’s old Bajoran resistance cell.

The Adversary (Episode 26)—Commander Sisko becomes Captain Sisko, just in time for things to get much, much worse with the Dominion.

Season 4

The Way of the Warrior, Parts 1 and 2 (Episodes 1 and 2)—Deep Space Nine gets a new Starfleet Security liaison in the form of a very familiar face: Worf! Oh, and some important head-hair disappears.

The Visitor (Episode 3)—A heartbreaking look at the potential future of Jake Sisko’s relationship with his father. Be ready to cry.

Hippocratic Oath (Episode 4)—Bashir and O’Brien find themselves in an ethical quandary when they’re tasked with exploring what it would mean to wean the Jem’Hadar off of the drug that sustains them for the Dominion: Ketracel White.

Indiscretion (Episode 5)—Stuck on an away mission with the one person she hates most in the galaxy, Kira is let in on one of Gul Dukat’s biggest secrets.

Rejoined (Episode 6)—Star Trek makes a bold (but brief) step forward in exploring queer themes when Dax finds herself feeling the emotions of a past life...when her former wife shows up.

Little Green Men (Episode 7)—Quark, Rom, Nog, and a few Ferengi pals accidentally find themselves zapped back to ‘40s Roswell.

Our Man Bashir (Episode 10)—Another light one, as Dr. Bashir indulges in a special holosuite program to envision himself as...actually, kinda one of the best Bonds that never was?

Homefront and Paradise Lost (Episodes 11 and 12)—Chase all that fun with a dark, moral dilemma: As tensions with the Dominion continue to rise and rise, Sisko is brought back to Earth to deal with a potential Founder infiltration at the very heart of Starfleet Command.

Crossfire (Episode 13)—As Kira rekindles a relationship with Shakaar and Quark continues to be, well, Quark, Odo finds himself caught in the titular crossfire of emotions.

Return to Grace (Episode 14)—Gul Dukat realizes the path he’s meant to be on, changing his relationship with Kira and with Deep Space Nine at large forever.

Sons of Mogh (Episode 15)—As Worf tries to help his brother bring honor back to their House, he finds himself drawn closer and closer to Dax.

Bar Association (Episode 16)—Rom learns the most vital lesson of all: Unionize your workplace, folks.

Accession (Episode 17)—Tired of Sisko’s reluctance to be the herald of the prophets, the Bajorans decide it’s time for a radical new Emissary.

Rules of Engagement (Episode 18)—After destroying a Klingon transport while on an escort mission, Worf finds himself in hot water with Starfleet and his people alike.

Hard Time (Episode 18)—A traumatized O’Brien finds himself haunted with memories of a two-decade prison stint he can’t remember.

For the Cause (Episode 22)—Garak makes a friend in Dukat’s daughter, while Sisko is hit with some troubling news: His girlfriend Kasidy may be a Maquis agent.

To the Death (Episode 23)—A mysterious new aspect of the Dominion comes into play when Sisko has to work with Vorta servant Weyoun to deal with some rogue Jem’Hadar.

The Quickening (Episode 24)—Bashir struggles with the limits of his medical expertise when confronted with a mysterious incurable disease.

Body Parts (Episode 25)—The Ferengi Commerce Authority rears its ugly head again, putting Quark in peril. Meanwhile, Kira becomes...involved in the O’Brien’s attempt to have a new child.

Broken Link (Episode 26)—Tensions finally fray between the Federation and the Klingons once more, as the Founders call Odo home to face a reckoning.

Season 5

Apocalypse Rising (Episode 1)—As the conflict with the Klingons gets worse, Sisko, Worf, Odo, and O’Brien go undercover to expose a Dominion agent within the Empire.

The Ship (Episode 2)—Capitalizing on the chance to seize a downed Jem’Hadar attack ship, Sisko finds himself in a precarious alliance.

Looking For Par’Mach In All The Wrong Places (Episode 3)—Love’s in the air on the Promenade, as Quark’s Klingon ex-wife comes aboard the station, and Worf and Dax realize their feelings for each other.

Nor the Battle to the Strong (Episode 4)—In his budding journalism career, Jake learns a valuable lesson: War? It’s pretty sucky.

Trials and Tribble-ations (Episode 6)—Star Trek’s best anniversary celebration ever, as our crew finds themselves flung back to events of the iconic episode “The Trouble with Tribbles.”

Things Past (Episode 8)—Odo, Garak, and Sisko somehow find themselves sent back to the time DS9 was Terok Nor...and Odo confronts what he did to get through the station’s Cardassian occupation.

The Ascent (Episode 9)—A tough bit of mountaineering sees Quark and Odo finally come to a better understanding of each other.

Rapture (Episode 10)—Bajor is approved for Federation membership, while Sisko is granted a dire vision from the Prophets.

The Darkness and the Light (Episode 11)—Kira is targeted when members of her old resistance cell start being killed off.

The Begotten (Episode 12)—When Odo finds an infant changeling, he finds himself reunited with his former mentor while learning how to look after it.

For the Uniform (Episode 13)—Sisko crosses some lines in a quest for vengeance against the Maquis.

In Purgatory’s Shadow and By Inferno’s Light (Episodes 14 and 15)—Everything, diplomatically, starts to go to shit when Worf and Garak are captured by the Dominion, Cardassia makes a choice, and a cold war starts to get very warm all of a sudden.

Doctor Bashir, I Presume? (Episode 16)—Bashir learns a shocking truth about himself from his parents.

Ties of Blood and Water (Episode 19)—Remember when Kira was almost brainwashed into thinking she was a Cardassian sleeper agent? Well, her “Dad” is back, leading to some lingering feelings about the passing of her real father resurfacing.

Ferengi Love Songs (Episode 20)—Love’s in the air (again), as Rom and Leeta go through a whirlwind engagement and Quark spies profit when his mother attracts the arousal of the Grand Nagus.

Soldiers of the Empire (Episode 21)—Worf is pulled between his people and his position once more when General Martok calls on him to be his first officer.

Children of Time (Episode 22)—Some time-travel shenanigans lead to the crew confronting their descendants and some tough choices.

Blaze of Glory (Episode 23)—Sisko has to temporarily bury his (rather sizable) hatchet with the Maquis to stop even more bloodshed.

Empok Nor (Episode 24)—DS9 goes a bit horror when Garak, O’Brien, and an engineering team try to scavenge the abandoned sister-station to DS9 for parts.

Call to Arms (Episode 26)—Rom and Leeta get married, which, naturally, leads to all-out interstellar war. Okay, so these events may be largely unrelated.

Season 6

A Time to Stand, Rocks and Shoals, Sons and Daughters, Behind the Lines, Favor the Bold, and Sacrifice of Angels (Episodes 1-6)—Phew! Deep Space Nine goes big with a tense, incredible, explosive serialized arc: With DS9 under Dominion and Cardassian rule, and with its Starfleet crew in retreat...until Benjamin Sisko decides its time to get his station back. War comes to Star Trek in a way unlike anything we’ve ever seen before.

You Are Cordially Invited (Episode 7)—As the dust settles in the battle for Deep Space Nine, Jadzia and Worf tie the knot.

Statistical Probabilities (Episode 9)—Bashir is entangled with some fellow genetically modified supergeniuses, as Starfleet tries to find a way to gain the upper hand in the Dominion War.

The Magnificent Ferengi (Episode 10)—Take a momentary break from all this horrifying warfare as Quark recruits himself a team of crack Ferengi miscreants to save his mom from Iggy Pop. I’m not joking.

Waltz (Episode 11)—An injured Sisko is trapped with Dukat on a mission, who undergoes a profound spiritual awakening.

Far Beyond the Stars (Episode 13)—In the 1950s, aspiring science fiction writer Benny Russell just wants his story about a future where a black man can command a space station to get published.

Change of Heart (Episode 16)—Trying to have the honeymoon they missed out on while on a dangerous mission, Worf and Jadzia face a trial by fire with each other.

Wrongs Darker Than Death Or Night (Episode 17)—Gul Dukat goads Kira with a traumatic revelation about her mother’s time under his servitude during the Occupation.

Inquisition (Episode 18)—Bashir is accused of treason by a branch of Starfleet he never knew existed: the Federation’s dirty secret, Section 31.

In the Pale Moonlight (Episode 19)—To change the tide of the war, Sisko dances with the devil. Just...just phenomenal Star Trek. Phenomenal television full stop.

His Way (Episode 20)—As his long-simmering feelings for Kira begin to overwhelm him, Odo gets help from an unlikely source: smooth-singing holographic cabaret act, Vic Fontaine.

The Reckoning (Episode 21)—When the Prophets call upon their Emissary in their endless conflict with the Pagh Wraiths, Sisko, Kira, and Kai Winn face a grim test of faith.

The Tears of the Prophets (Episode 26)—The Federation makes a decisive move in the Dominion War, Gul Dukat gets his revenge, and the crew of DS9 loses one of their own.

Season 7

Image in the Sand and Shadows and Symbols (Episodes 1 and 2)—Things change on DS9, as a broken Sisko goes on leave, Kira has to deal with a diplomatic crisis, and Worf mourns.

Afterimage (Episode 3)—A fresh-faced Starfleet counselor makes their way to Deep Space Nine. Oh, did we mention her name is Ezri, and she’s the latest host of the Dax symbiont?

Take Me Out to the Holosuite (Episode 4)—Sisko deals with a racist Vulcan the only way he knows how: challenging him to a baseball match.

Treachery, Faith and the Great River (Episode 6)—Odo finds himself having to protect a defector from the Dominion.

The Siege of AR-558 (Episode 8)—War. What is it good for? Nog learns that the answer is “absolutely nothing.”

Covenant (Episode 9)—Dukat sets the stage for a spiritual reckoning when he captures Kira alongside a cult of Pah-Wraith worshippers.

It’s Only a Paper Moon (Episode 10)—Recovering from PTSD, Nog turns to Vic Fontaine.

Chimera (Episode 14)—Odo faces a familiar mirror in a changeling who did not live under the Founder’s thrall, only to find their opinion on “solids” is radically different.

Badda-Bing, Badda-Bang (Episode 15)—For one last time, DS9 has a bit of fun, when the team comes together to stage a glam heist and save Vic Fontaine’s holographic hide.

Inter Arma Enim Silent Leges (Episode 16)—Bashir finds himself keelhauled into working with Section 31 again, to play a game of cloak and dagger with the Romulans.

Penumbra, ‘Til Death Do Us Part, Strange Bedfellows, The Changing Face of Evil, When It Rains..., Tacking Into the Wind, Extreme Measures, The Dogs of War, and What You Leave Behind, Parts 1 and 2 (Episodes 17-26)—It all ends. The Federation and the Dominion come to a head, Kira helps the Cardassians make another vital choice, and Captain Sisko faces a destiny he’s been running from since Deep Space Nine first began.

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