Say what you will about DS9, it delivered plenty of what the f*** moments over its seven year run. Spoiler level: you should have watched this years ago.
5) Back to the Mirror Universe
Star Trek: The Next Generation, in all of its glory, never found its way to the Mirror Universe. Their loss was DS9’s gain in the first of several trips through the looking glass. Kira and Bashir inadvertently catch up with the alternate reality first visited by the Original Series that boasted goatee Spock and an agony booth. Things haven’t gone well those tyrannical humans since last we met. They’re slaves, laborers, and markedly less aggressive under the pointy boot of a Klingon-Cardassian alliance. Nana Visitor shines as her maniacal doppelganger.
Season 2, Episode 23, “Crossover”
4) Death of Dax
Season 6 ended with a wormhole-sized bummer as Jadzia Dax, original crew member and fan-favorite, was fitted for a torpedo coffin. Fans knew actress Terry Farrell was leaving the show. Not to mention, being a joined species, it was a forgone conclusion the “Dax” slug would live on in another host. Still, DS9 decided to really twist the bat’leth on her send off. Jadzia finds out it’s possible to procreate with her Klingon husband (the almighty Worf) and ventures into a Bajoran temple to say “thanks”. Unfortunately, she’s greeted by a possessed Gul Dukat who zaps our spotted science officer into the sunset.
Season 6, Episode 26, “Tears of the Prophets”
3) Bashir Reveals
Alright, technically these are two moments. But Dr. Bashir had a big 5th season. First, we find out the DS9 doctor has been a Changling for the last few episodes (an interview with Ron Moore said the ol’ switcheroo happened before S5, E10 “Rapture”). After Worf and Garak are Shawshank’d on an asteroid they find a one-eyed General Martok and disheveled Bashir wearing a dated uniform.
Once back on the station for a few episodes, Bashir’s folks stop by for a visit as does the man behind the Emergency Medical Holographic program who wants to model the next iteration of the EMH on our good doctor. As it turns out, we get an intergalactic Maury Povich reveal as the audience let’s out a collective WTF after finding out Julian is genetically-engineered. Always has been. Smarter and better at darts.
Season 5, Episode 14, “In Purgatory’s Shadow”
Season 5, Episode 16, “Doctor Bashir, I Presume”
2) Sisko-Romulan Fakeout
So, the Federation was getting its ass kicked in the Dominion War. As the casualty lists keep pouring in, Captain Sisko figures he has to convince the Romulans to join the dance. Naturally, they’d rather sit around and sift through the ashes when the war is over. Damn Romulans. Anyway, Sisko goes sideways with desperation and enlists the living spy novel and Cardassian outcast Garak to use his tailored brand of subterfuge. The plan blows up in their face, by design. In the end, a Romulan senator is murdered and it’s all pinned on the Dominion. They join the war and Sisko confesses the whole plan in his log…
Season 6, Episode 16, “In The Pale Moonlight”
1) Enter: The Jem’Hadar
The season 2 finale of DS9 introduced a villainous band of super soldiers with badassery not seen since the Borg. The Jem’Hadar, foot soldiers of The Dominion, would plague our heroes until the series finale. Long before the massive war that would decide the Alpha Quadrant, these drug addled gladiators drew first blood in a jaw-dropping fit of destruction. The U.S.S. Odyssey was set to retrieve Sisko, Jake, and Nog in the Gamma Quadrant. All kinds of hell breaks loose and in a fire battle a lone Jem’Hadar ship intentionally smashes into the Galaxy-Class ship, sending tiny pieces of it across the system. Yeah, the Dominion means business.
Season 2, Episode 26, “The Jem’Hadar”