As Kira's double plots to become the Emissary of the Alternate Universe, Taran'atar starts to fight his new programming to develop free will.

Once again, I'm left with the sense of loss, how I could have read an entire book and seem to be no further ahead in character development or story motion, except perhaps in the last couple of pages.

What is the Soul Key? It is a shard of an orb, as shards were taken from all the orbs in the alternate universe before they were destroyed by the evil human empire that Spock helped to bring down. A prophecy held that the shard would bring about destruction, so the person who took the shards somehow crossed over to the universe we know, and hid it in a Bajoran village, where the woman with Kira's face stole it and destroyed the whole village in Trill/Bajor. A cruel trick played by trying to interpret prophecy!

What does it do? We don't know, yet. Iliana Ghemor, pretending to be Intendent Kira, tried to use it to fool the Prophets into turning her into the Emissary of that universe, since Sisko is dead. But it didn't work, and they healed her soul instead, instead. That could be a part of it. By the end of the book, she has become the "Fire" among the Ascendants, the race that wants to kill their own gods, the prophets, as well as any others who worship them. But how did she get there in the midst of them? The Prophets have only ever transported a fleet of Jem'hadar ships. What makes Ghemor so special that they could transport her to the planet they plan to stage from?

Before that happens, however, we get a bunch of protracted scenes showing how insane Iliana Ghemor from our universe really is. Her part of the story takes up as Fearful Symmetry ended, at the end of What You Leave Behind. From there, she observes the state of the galaxy, tries to take advantage of it, until she learns of Taran'atar, and is told she might be able to use the techniques the Obsidian Order tested on Jem'hadar at Harkoum on him. She does, successfully bonding him to her instead of the Founders.

Then she steals the orb fragment, and waits for Taran'atar to come to her, after which she leaves for the Alternate Universe, all of which we saw from our perspective in Warpath and the books that preceded it. The author even mentions the Gateway book Demons of Air and Darkness. It's nice to know the earlier books aren't being forgotten, when preparing for this new war.

In the Alternate Universe, Ghemor as the Intendent gets some superficial scenes in front of Dukat and Martok, as well as the rebels on Terok Nor. She actually bombards the capital city of Bajor, Ashalla, pretending the rebels did it. When she discovers Kira and Vaughn, who transported from our universe at the end of "side 1" of Fearful Symmetry, she pretty much destroys the sanctuary, capturing several of its leaders.

I really think the mirror universe has run its course. Hopefully the authors realize this, and have given the universe a good wringing here. For we meet even more characters we already know from our side. The coincidences are ludicrous, and I think the authors know it. Vaughn comments on the likelihood of meeting Prynn, which I find doubtful, as if he expected it. He also meets himself, a dying man, and the leaders of the Bajoran secret religious resistance, Winn and Opaka, and Jaro from the second season Bajoran rebellion against the Federation. Shar also appears for a short moment! The likelihood of any of them being born after Spock's actions in Mirror Mirror are so remote, and to find them on Bajor is  even more so. But it's something we learn to expect, so we accept it. But now I think it's been done to death.

As for our characters, not much happens on Deep Space Nine. Ezri, Nog and Bashir figure out how to get the wormhole to expel them into the Alternate Universe, but with very little effort. The alternate Iliana Ghemor gets a crazy idea that she should make herself look like the Intendent, too, and joins them for the ride back. They also perfect the hand-held device that was supposed to deprogram Taran'atar, which turns out to be useless, because he has already deprogrammed himself. Afterwards, Kira lets him go, and he tries to make his way back to the Founders, not realizing what happened to them, of course, in Ferenginar/Dominion.

The most interesting part of the book came from Kira and Vaughn's interaction with the sanctuary, where Winn and Opaka keep the remaining orb fragments, and where Vaughn is forced to kill his mirror image so that Prynn could get away. What was that for? Vaughn seemed to understand a little, but I don't. Was he actually supposed to become the Emmissary? Did the Prophets want Vaughn instead of Iliana? Regardless, I don't see how that progresses either the story of Vaughn's character, or the alternate universe. Because the two Ghemor's ended up becoming Emissary, instead. Nothing Vaughn did in the alternate universe made any difference, except that he came back hating Sisko. Hopefully we will get more information in the next book.

When the Intendent attacks the sanctuary, Kira and Vaughn are captured, though Prynn, Opaka and the shards escape. The prisoners are brought up to Terok Nor, which the rebels surrendered after further threats to bombard Bajor on their behalf. There, Taran'atar promises to rescue Vaughn, and Kira is taken to see Ghemor. As the Defiant from our universe emerges from the wormhole, Ghemor's plans start to fall apart, so she blows herself, the alternate Ghemor and our Kira out the airlock and into the wormhole, where they meet the Prophets together.

Kira is sent back to the Defiant, the alternate Ghemor to Terok Nor as "the voice", and the formerly insane Ghemor from our universe, presumably healed (though I'm not certain, as she is leading -sabotaging? - a bunch of fanatics against the Prophets), to the Ascendants as "the fire".

I felt that too much time was spent on the insane Ghemor, and not enough on the characters who originally brought DS9 to us, who played only cursory roles. There is a lot of fake swearing, which sounds fake and is not needed. And I'm starting to really wonder if the DS9 novels are really worth my time. Still, I'm curious about what will happen next, so I'm guaranteed for a while longer. I just hope we get some real character development and real story, as we did in several of these sequel novels.