Star Trek: Deep Space Nine always loved shocking fans and few times did they rock the series as much as an epic two-part sequel!
By the fifth season of Star Trek: Deep Space Nine, the series had entered full swing into the Dominion War storyline. That included the complication of the Federation-Klingon peace breaking down, so the Klingons were a threat. That's not mentioning the Maquis, the huge militia of former Starfleet officers fighting the Cardassians on their own, which had conflicts with the Federation.
In many ways, this was coming off the big two-part third-season storyline where the Dominion destroyed a joint Romulan-Cardassian fleet. That had some major implications, but two years later, DS9 was doing a follow-up that ended up being just as huge a game-changer for the Trek universe!
"In Purgatory's Shadow/By Inferno's Light"
The 14th and 15th episodes of Season 5 took a seemingly obvious storyline and transformed it into an epic tale with genuine shocks for the audience. That included one twist that would form one of the most vital arcs in DS9 and thus one of the best for all of Star Trek.
A search begins
The tale opens with the crew getting an old coded Cardassian transmission. Garak claims it's just data and it doesn't take a detective to know he's lying (because it's Garak). When he tries to hijack a shuttle, a phaser-wielding Bashir is waiting for him.
Put on the spot, Garak confesses the message was actually a cry for help from his old mentor, Enabran Tain, last seen on an exploding bridge during the Dominion massacre of the Cardassian-Romulan fleets. That he could survive seems impossible, but as Garak relates, anyone who can survive twenty years running the Obsidian Order could survive anything.
Garak says he owes Tain and so wants to go on a rescue, pointing out there could be other Dominion prisoners to save. Sisko agrees with Worf going with Garak, which upsets Dax. Meanwhile, Garak continues to flirt with Dukat's daughter, Ziyal, with Dukat (on the station for repairs to his ship) naturally not pleased, which almost comes to blows with Garak.
We get some wonderful banter between Garak and Worf, with Garak pushing for a Starfleet application only to reveal he was lying. The humor ends when they find a massive Jem'Hadar fleet on the other end of the wormhole and realize they're planning an invasion of the Alpha Quadrant.
The pair manage to warn DS9, who prepare for the attack with Dukat urging Ziyal to come with him to Cardassia, which she refuses. The way Dukat tells her of something coming is a bit foreboding…
Get ready for a shock reveal
Worf and Garak are captured by the Dominion and brought to a prison camp. Among the prisoners is Martok, the Klingon warrior who had been impersonated by a Changeling in the season 5 premiere. He brings them to a badly ill Tain.
On the station, Sisko sums up how weak the Alpha Quadrant is between the Dominion, Klingons, Maquis, and even the Borg in First Contact. That's pushing him to the extreme action of sealing off the wormhole (careful not to hurt the PRophets aliens) to cut off Dominion support.
Back at the camp, Worf is shocked when another prisoner is brought in: Julian Bashir. Not only that, but because he's wearing an older uniform and has been there a month, this means the Bashir we've been watching for the previous four or five episodes has been a Changeling.
It wasn't just a surprise to viewers as Alexander Siddig related he was just as stunned to read the script. He was at first annoyed as if he'd known he was playing a Changeling, he might have adjusted the performance. However, Siddig realized the writers were smart as he might have given the twist away too early (and, of course, an imposter would be careful to perfectly replicate Bashir to fool everyone).
Garak and a dying Tain try to talk things out, with Garak complaining to Bashir about how he did so much to make Tain proud, only for the man to dismiss him. When Tain tells Garak to escape for revenge, Garak says he will "on one condition: That you don't ask me this favor as a mentor, or a superior officer… but as a father asking his son."
Yep, Tain is Garak's father. It instantly explains why Garak would go to such lengths to try and rescue Tain, why he followed him before and why he always wanted to make him proud. A dying Tain talks of a memory of Garak as a child before he passes on. With that closed off, Garak declares it's time for a breakout.
And it's a good time for it too. Back at DS9, they try to seal the wormhole, but the imposter Bashir has sabotaged the emitters. The crew thus looks in horror as a massive Dominion fleet begins the invasion and a perfect cliffhanger.
Welcome to the new Cardassian threat
As the second part opens, the crew is ready for an attack, only to be surprised when the fleet ignores the station and heads toward Cardassia. When Dukat's ship follows, Kira calls on him not to be a hero. Dukat says that's not a problem as he's not attacking the fleet, he's going with them. It seems for months, Dukat has been pulling off secret negotiations, with the result being that Cardassia is now part of the Dominion.
This was another curveball to fans, who had just come to accept Dukat as an anti-hero type. He was still sinister and scheming yet seemed softened by his daughter and fighting for acceptance. Instead, the writers wanted to remind fans that at his heart, this was an opportunist willing to sacrifice anyone and restore him to pure villainy. Dukat himself summed it up by telling Kira, "You and I on the same side? It never quite felt right."
At the camp, all the Cardassian prisoners are released with the exception, of course, Garak, thanks to the tiny issue Dukat hates his guts. Dukat himself makes a grand speech as the new leader of Cardassia, promising to wipe out the Klingons, Maquis, and anyone else who threatens them.
He lives up to his word as Chancellor Gowron shows up with a battered Klingon fleet. Sisko is able to convince Gowron to resign the Khitomer Accords and revive the Klingon-Federation alliance while the Bashir imposter is making some moves around the station.
Much of the episode is built around Worf being forced to battle one Jem'Hadar soldier after another while Garak is attempting to rejigger some communicators to get the runabout to beam them out of their cell. It's complicated by the revelation that Garak is extremely claustrophobic and stuck doing this in a tight space.
Dukat and Sisko have a chat where Dukat breaks all records in justifying his actions for the greater good as it spares Cardassia from destruction. He even offers to have the Federation join the Dominion as well. When Sisko naturally turns him down, Dukat threatens a full-scale attack on DS9.
The thrilling climax
The plotlines come together as Worf and the Jem'Hadar leader fight it out while Garak is able to get the transporter working. Guards arrive with a Breen prisoner killed fighting them while Worf refuses to quit to the point the Jem'Hadar declares "I can kill him but I cannot beat him," showing the code of honor he has. That has him killed, but luckily, Garak is finally able to get the transporter working so the rest escape.
Back at the station, the Romulans have surprisingly joined the Federation and Klingon fleets while the Changeling Bashir takes over a runabout. Sisko is confused that the supposed huge Dominion fleet is showing up on sensors but not in person. He then gets an SOS from the real Bashir, warning him of the imposter as the rogue runabout is heading to Bajor's sun.
Sisko realizes there is no invasion fleet as the whole point is for the Bashir imposter to use stolen materials for a massive bomb that will cause Bajor's sun to go nova, taking out Bajor, DS9 and the combined fleets. The Defiant is able to tow the shuttle away before it reaches the sun, only killing the imposter. "Armageddon will have to wait for another day."
The fallout has the Klingons fully back in peace with the Federation, with Martok heading up a permanent Klingon garrison on the station (and thus giving us another great regular character). There's a warm reunion between Garak and Ziyal and a little light-hearted talk with O'Brien joking he should have known about a fake Bashir as "he was easier to get along with." The final scene has Dukat and Sisko talking again, with Dukat disowning Ziyal and he and Sisko knowing they're going to face each other one day.
This two-parter is one of the best tales in all of DS9. It's a terrific showcase for Garak, explaining his true parentage and the touch of him being afraid of enclosed spaces is a humanizing quality for him. It's still Garak with bits like how he overcomes his fears as "the cowardly Cardassian would ruin General Martok's song." Off that, Martok is instantly captivating with his gruff humor and veteran aura and no wonder he quickly became a fan favorite.
The twist of Bashir having been impersonated by a Changeling was a clever touch as we get the tension of knowing about him, but the characters are clueless. The revelation of the Dominion's true plot was also a nice bait and switch as we expect a grand battle that never comes. All this and one of the most epic Worf moments ever as he refuses to quit against this gauntlet of foes.
Of course, the biggest moment is Caradassia joining the Dominion. The ramifications this would have for the Trek universe were big, starting with the Klingons as allies again. Bigger is how it restores the Cardassians to a huge threat and long-term effects like how they soon wipe out the Maquis (which would play into Voyager as well).
Having Dukat return to his villainous roots also works perfectly. As he himself says, it never quite felt right for him to be a good guy, he was always making the universe about himself and going to whichever side felt like the winners. In this case, it was the Dominion and becoming the leader of the world that had earlier cast him aside was too good to pass up.
Sisko's line on "delaying Armageddon" is more foreboding with future storylines as well as Martok noting how the fate of the Alpha Quadrant rests on a small world no one had heard of years before. Thus, this two-parter not only changed the game for Deep Space Nine but set up the arcs and themes that would dominate for the rest of its run and still stand as a great two-part tale for any Trek fan.
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