This character is a member of the O'Brien family native to the mirror universe.
For the primary universe counterpart, see Keiko O'Brien.

In the mirror universe, Colonel Keiko Ishikawa was a female Terran operative of Memory Omega who became a slave and eventually an overseer on the Klingon-Cardassian Alliance mining colony Korvat.

She was trained by an elderly Vulcan woman named T'Lara. T'Lara had once shown her holovid footage of Grand Admiral Spock's usurpation of the throne of the Terran Empire in 2277, which he accomplished by making his predecessor Hoshi Sato III vanish into thin air. (DS9 - Mirror Universe novel: Saturn's Children)


In 2358, shortly after her arrival on Korvat, she began a relationship with a Cardassian slave overseer named Glinn Broca. Three years later, she had him arrange a meeting with the colony's commanding officer Gul Zarale, at which she informed him of the plot to kill the Klingon overseer Kozak. After the relevant slaves were taken into custody, Keiko suggested to Zarale that he spare their lives as further deaths in Kozak's section would only result in increased inefficiency. He followed her advice. Over the course of the next four years, Keiko gradually gained Zarale's trust and was able to subtly manipulate him, as she had done with Broca. By 2365, Kozak had become a drunkard who was no longer able to perform his duty to the required degree. Given that he had been found derelict, he was relieved of his position and executed by two Cardassian guards at Zarale's orders. Keiko succeeded Kozak as the overseer. In 2372, her fellow Memory Omega operative Tasha Yar arrived on Korvat. She soon made contact with Keiko and pretended to grant sexual favours in case they were being monitored. The message, contained in a tattoo on one of Yar's legs, was written in Japanese calligraphy: "Our efforts proceed apace. Rebellion growing in Bajor sector. Proceed with training and liberation. Destination: Terok Nor." Yar and Keiko began training dozens of slaves, including Tiron and Sam Bowers, in combat tactics in preparation. In 2375, after three years of meticulous planning, the two Memory Omega operatives staged a slave revolt in the Korvat mines. Approximately 200 slaves managed to reach the transport bay where Keiko and Yar each piloted one transport, each containing about half of their complement. However, Keiko regretted not killing Zarale in his sleep when she had the opportunity. Although the transports were both able to reach orbit and set course for the Badlands, they came under attack from a Klingon battle cruiser. As the starboard impulse engine of Yar's transport went offline and began leaking plasma, she provided a distraction which allowed Keiko's transport to escape to Terok Nor, the headquarters of the Terran Rebellion, before her ship was destroyed by the Klingons. (DS9 - Mirror Universe short story: "A Terrible Beauty")

Within months of arriving on Terok Nor, Keiko struck up a romantic relationship with the Rebellion's leader, General Miles "Smiley" O'Brien, who in turn began to trust her more and made her his second-in-command, with the rank of commander. This move was frowned upon by other rebel leaders, such as Generals Zek and Julian Bashir, and hurt O'Brien's standing in the organization. With the deaths of most of the Rebellion's leaders and capture of Zek and Bashir at Empok Nor, Keiko found herself increasingly relied on by the Rebellion's new leadership. She helped expose Sito Jaxa as an Alliance spy, then disintegrated her for trying to kill O'Brien and General Michael Eddington. In the later aftermath of the disaster at Empok Nor, Keiko and Eddington helped restore O'Brien's hope and convinced him to continue leading the Rebels to their imminent victory over the Alliance. (DS9 - Mirror Universe novel: Saturn's Children)

In January 2377, after Lieutenant Nog was able to establish communication between Terok Nor and Deep Space 9 in the primary universe, Smiley introduced Keiko to Nog, Captains Benjamin Sisko and Kira Nerys, Doctor Julian Bashir, Lieutenant Ezri Dax and the Iliana Ghemor of her own universe. Based on their body language, Bashir determined that the she and Smiley were lovers. He mused that there were "soul mates in any universe" given that their counterparts, Miles and Keiko O'Brien, were happily married in the primary universe. (DS9 novel: Fearful Symmetry)

The crew of DS9 warned the rebels that the Iliana Ghemor of the primary universe had killed the Intendant, assumed her identity and attended to become the Emissary of the Prophets by discovering the Bajoran wormhole. However, after Keiko detected twelve Klingon ships including the IKS Negh'Var approaching the station and Smiley had ordered his crew to prepare for a planetary bombardment of Bajor starting with its capital Ashalla, the conversation was cut short by the primary universe's Ghemor. (DS9 novels: Fearful Symmetry, The Soul Key)

Dark Passions continuityEdit

Keiko Ishikawa was presented as a gift from B'Elanna, Intendant of the Sol system, to Deanna Troi, Intendant of Betazed. (TNG novel: Dark Passions)

Star Trek Online continuityEdit

Miles and Keiko were the parents of James O'Brien, who later became a captain in the restored Terran Imperial Starfleet. James later murdered Miles, becoming the leader of the Terran Empire. (STO mission: "Crack in the Mirror")



Terok Nor personnel
Cardassian Union
Cardassian Guard
and Cardassian-allied personnel
Basso TromacBoheekaCorat DamarDatarSkrain DukatDulathHadarMavekNaratOranParekSigol RusotGaten RussolThrax Sa'kat CardassianUnion
Bajoran Provisional Government
and Bajoran-allied personnel
JabaraKellec TonKira NerysOdoRom BajoranEmblem
Dominion (2374) Weyoun DominionEmblem
Mirror universe Terok Nor personnel
Klingon-Cardassian Alliance Elim GarakKira NerysOdoJennifer SiskoTelok KlingonCardassianAlliance
Terran Rebellion Julian BashirSam BowersJadziaMichael EddingtonKeiko IshikawaLeetaEnrique MuñizNogMiles O'BrienJennifer SiskoLuther SloanLon SuderEzri TiganTiron Terran symbol
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