DS9 Flashback: Crossover

There was a time when "Mirror, Mirror" was just a one-off episode of the original Star Trek. It was beloved by fans, and known even among non-fans (goatee = evil), but it was not a well that Star Trek had ever returned to. Then came the Deep Space Nine episode "Crossover."

When a runabout passes through the wormhole while experiencing an engine malfunction, Kira and Bashir are transported to a dark and sinister parallel universe. The Klingons and Cardassians have united, with Bajoran assistance, to subjugate the descendants of a once-mighty Terran Empire. All this is the consequence of a prior "crossover" decades earlier, when the James T. Kirk of our universe persuaded the Spock of theirs to pursue more peaceful ways. Bashir must stay alive while slaving in ore processing, as Kira tries to convince her mirror self to release them to return where they belong.

This is not the first time a Star Trek spinoff staged a sequel to a classic episode. Quite illogically, The Next Generation did so with their very first one hour episode, "The Naked Now." According to show runner Michael Piller, "Mirror, Mirror" sequels were pitched multiple times over the years, with him always resisting. Eventually the Star Trek spinoffs established their own identities well enough that looking backward probably felt less risky. And the lure of finding out how Kirk's influence changed the mirror universe finally proved irresistible.

The mirror universe would ultimately be visited several more times in Deep Space Nine, become the subject of a two-part episode of Enterprise, and fuel the first season of Discovery. But it seems clear that there were no long-term plans at the time "Crossover" was made. Had the writers known better, they surely would not have chosen to kill both Quark and Odo (the latter in a marvelous practical explosion of a wax model), cutting two series regulars out of the ongoing fun.

This take on the mirror universe is far less action-packed than later episodes would present. "Crossover" is actually a surprisingly talkie episode -- or perhaps not surprisingly, when you consider that this episode, like the original "Mirror, Mirror," is interested in making a social point: brutal authoritarian governments will inevitably crumble, either from within or without.

That's not to say that this episode is all talk and no fun. It's tons of fun, mostly in how it lets most of the regular cast cut loose as they play their mirror counterparts. Rene Auberjonois gets to play Odo as a full-on baddie. Armin Shimerman serves up a noble Quark, operating an "underground railroad" to free humans. Avery Brooks goes broad as a swaggering, piratical Sisko, giving us a hint of how much more compelling the real Sisko would become in later seasons (once the writers quit trying to hammer him into the Starfleet mold so hard). Guest star Andrew Robinson drops Garak's usual mask to play a less subtle villain.

But no one is having as much fun here as Nana Visitor. The mirror universe "Intendant" Kira is a slinking hedonist oozing camp over every scene. It's such a vivid performance, it may well be The Main Thing inspired a revisit to the mirror universe next season. Visitor does great work as original Kira too -- putting up with Bashir's annoyances in the teaser, lying to mirror Quark to manipulate him, and playing convincingly off herself in split-screen scenes with the Intendant.

By placing Kira at the center of the story (rather than a Starfleet character), the writers have a way to work in exposition for viewers who may not know the original "Mirror, Mirror." For the viewers who do know it, they pile on the homages. Garak tries to advance in rank by assassination, just as Chekov attempted in the original episode. The logo on the Terran jumpsuits is the original series' Terran Empire logo, with the sword removed. There are multiple explicit references to Kirk and Spock (plus a mention of Lursa and B'Etor for Next Generation fans). Tons of fairly seamless fan service.

As with "Necessary Evil," the look of the station is completely transformed through set decorations and extreme lighting changes. Characters get brand-new costumes, from the Intendant's iconic bodysuit to a collar and belt for Odo that Rene Auberjonois liked so much, he lobbied to add them to his regular uniform at the start of next season.

Other observations:

• I'd argue that director David Livingston went a bit too far with the camera work when Kira and Bashir first arrive in the mirror universe. The extremely low angles when Klingons board the runabout do make it clear something is different now... but I think too clear.

• We don't get mirror versions of Bashir, Dax, or Jake in this episode. Later mirror universe episodes would give us the first two, while establishing that Jake simply doesn't exist there.

• The original plan was to put Worf in this episode, but Michael Dorn could not be freed up enough from filming the final season of The Next Generation. His lines were given to Garak. This arguably worked out for the best, allowing for a different take on Mirror Worf when Dorn actually joined the Deep Space Nine cast a few years later.

Despite the big money spent on this episode, it doesn't feel all that big to me, perhaps due to the relative lack of overt action (particularly space battles). I'd probably grade it a B... though I feel like an extra "+" is earned by the clear fun the actors have in their different roles. I don't know that I find the mirror universe as compelling in the long-term as various Star Trek writers clearly did, but that's nothing to hold against this episode.