Book #2 of 3 in the Star Trek: Terok Nor miniseries.
This miniseries details events on the Space Station before Terok Nor became Deep Space Nine, while it was occupied by Cardassia. "Eighteen years into the Occupation, a new star rises in Bajor’s sky. It is the seat of power in this system, a place of slave labor and harsh summary judgments, the symbol of Cardassian might and the futility of resisting it. But even as the gray metal crown of Terok Nor ascends to its zenith, ragtag pockets of Bajoran rebels—including a fierce young fighter named Kira Nerys—have begun to strike back at their world’s oppressors, and they intend to show the Cardassians that the night belongs to them."
Elim Garak, under the cover of his codename, Agent Regnar, plays a very, very minor role.