Fearful Symmetry, written by Olivia Woods, is a novel in the Deep Space Nine Relaunch.
In our universe, a Cardassian sleeper agent called Iliana Ghemor was once surgically alltered to resemble and replace Bajoran resistance fighter Kira Nerys. That plan never reached fruition, and the fate of the agent remained unknown -- until now. Robbed of the past sixteen years and on the brink of madness, Iliana Ghemor is back with a vengeance. She has already made one attempt on the real Kira's life, and now the Deep Space 9 crew must somehow must stop the false Kira without derailing the delicate flow of history that must unfold if two universes, and countless others, are to survive.