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Cadet Training: "Crossover"

Our deep dive into Mirror Universe episodes continues with a look back at DS9's first Mirror hour, "Crossover"

Deep Space Nine "Crossover"

The Star Trek: Deep Space Nine episode "Crossover" ushered in a return to the Mirror Universe, the parallel dimension previously introduced in "Mirror, Mirror" from Star Trek: The Original Series. The realm's latest depiction offered a subtler take on good versus evil, reflecting the shifting loyalties and political intrigue that sprouted throughout DS9's seven-year run. Cadets, let's catch up on the situation and learn what transpired after Captain Kirk's visit that occurred roughly a century earlier.

The Second Crossing

The Alliance

Due to a plasma injector leak in their runabout's warp core, Major Kira and Dr. Bashir exited the wormhole to find... nothing. Deep Space 9 did not stand guard over the aperture, but Terok Nor was instead detected orbiting Bajor. Escorted to the station by a Klingon Vor'cha-class cruiser, the pair met a welcoming party from the Klingon-Cardassian Alliance, an organization that ruled the entire quadrant. Those present included Mirror Garak in his position as Terok Nor's first officer and Intendant Kira as the Bajoran sector's commander.

The Intendant took an immediate interest in Kira, bringing her counterpart to the office in Ops to explain exactly where the major had ended up. Kirk's advice to Mirror Spock regarding reforms for the Empire apparently struck home in "Mirror, Mirror," as the I.S.S. Enterprise officer rose to prominence as the commander in chief, spoke about peace, and led a disarmament movement. The Klingons, Cardassians and Bajorans took advantage of the docile Empire by forming a new military alliance, establishing their dominance over the quadrant and enslaving most Terrans.

Face to Face

Deep Space Nine

In "Mirror, Mirror," the U.S.S. Enterprise crew members who arrived in the Mirror Universe never interacted with their aggressive doppelgängers. "Crossover" broke that barrier, as the dialogue between Major Kira and the Intendant actually drove the plot forward. Mirror Garak's assessment that the Intendant loved Kira provided the intriguing theory that, in a galaxy filled with treacherous schemes, one could only rely on themselves. Always an intuitive observer, Garak remarked, "Who else could she share her deepest secrets with, tell her troubles to... trust with her life?"

Influential Reflections

Deep Space Nine

While cadets such as Julian Bashir read about Kirk's transporter accident at Starfleet Academy, the first crossover event influenced the Mirror Universe to a much greater extent. In addition to the galaxy-wide ramifications brought about by the Terran Empire's pacification and the Klingon-Cardassian Alliance's rise, Kirk's journey touched lives on a personal level. From the Intendant to Mirror Quark, most people seemed acquainted with the story. The Intendant went so far as to claim, "On my side, Kirk is one of the most famous names in our history."

Major Kira and Dr. Bashir initially planned to recreate Kirk's transporter mishap to return to their reality, but the Intendant soon trampled those hopes. Engineers in the Mirror Universe redesigned transporters after the initial crossover to prevent future breaches, and the Alliance enacted a protocol to kill any infiltrators from other dimensions on sight. Such precautions indicated the extent to which Kirk, McCoy, Scott, and Uhura affected the bearded Spock and the balance of power in the region. The regulations stood in stark contrast to the simple mention that Kirk's exploits received in Dr. Bashir's Starfleet Academy studies.

Shards of Evil

Deep Space Nine

Most Terrans in "Mirror, Mirror" acted in a savage manner, but that side's Spock and Marlena Moreau also exhibited more compassionate traits. "Crossover" expanded on this notion, bringing DS9's signature moral ambiguity and fragile accords into play. The Intendant spared a Terran escapee's life, yet quickly disregarded Quark's pleas for mercy. Whether a well-conceived deception or a character flaw, the station commander's vicious designs manifested in a subtler fashion than the ruthlessness displayed by the Terrans that Kirk encountered 100 years prior.

While the Klingon and Cardassian foot soldiers expressed attitudes quite similar to those in our universe, Mirror Garak and Mirror Odo appeared to amplify their prime compatriots' qualities. First officer Garak's manipulative tactics and willingness to betray the Intendant surfaced as connections to a certain humble tailor's time in the Obsidian Order came to light. Constable Odo's fondness for the law intensified under Mirror Odo, whose iron fist ensured that Terran prisoners behaved and remained productive in the ore-processing facility. Since Mirror Quark's death occurred off-screen, the evil Changeling enjoyed the honor of being the first main Mirror character to die in plain view during the Terran revolt.

The Heart of the Matter

Deep Space Nine

On the spectrum's other end, the Mirror Universe's Benjamin Sisko, Miles "Smiley" O'Brien, and Quark each embodied certain attributes present in their prime reality alternates. As a privateer, Mirror Sisko's swashbuckling ways evoked Commander Sisko's adventurous persona, while his decision to stand against the Intendant and aide Kira and Bashir in their escape lined up with the commander's steadfast leadership. Smiley's meekness blossomed into a dream for a better life after Bashir revealed Chief O'Brien's status as a family man and Mirror Sisko offered him a position with his merry band.

Mirror Quark's nobility emerged sooner than that of our own beloved Quark, but the bartender's role in ferrying Terrans from Terok Nor paralleled Quark's brave support for the resistance's struggle against the Dominion's occupation of Deep Space 9. Ironically, Prime Quark ended up freeing Major Kira, Rom, Leeta and Jake Sisko from imprisonment in "Sacrifice of Angels." Fortunately, the major also proved elusive in "Crossover," escaping through the wormhole with Dr. Bashir aboard their runabout and arriving safely back at their own station.

And the Mirror Universe's fate? That tale shall be continued...

Jay Stobie is a freelance science fiction writer who contributes articles to the official Star Trek website and Star Trek Magazine. He can be found on Twitter at @CaptStobie and Instagram @JayStobie.