Quick-take: Bad conclusion to a well-written series.
No time for a refresher course, this book dives right in. I reread the last part of the previous book before starting this one. "The Interdependency" has a complicated plot line. There are political maneuverings (aka "assassination attempts", collapsing transportation channels (called "the flow"), and a human-turned-computer-turned-spaceship. All kinds of fun stuff.
Book 3 spent a bit less time on Emperox Grayland II to instead follow Kiva Lagos around. She is a bad-mouthing, quick-thinking force to be reckoned with. She gets captured, escapes, and captured. The head of an important house/guild really does not like her. Kiva has a really important ally though, the Emperox. We see Emperox Grayland's relationship with Marsh grow. That stuff usually makes me cringe, but this was well down and actually quite cute.
As I was reading, I noticed none of the plot lines closing, and I was close to running out of pages. How is this going to end? I thought this was a trilogy. I'm about to get really mad here if there is no ending. Well, John Scalzi pulled a rabbit out of a hat. He did end it, sorta. That ending simply was not satisfying. The Epilogue left some BIG story gaps. How about, I don' t know, actually telling what happens when all the flows collapse? What happened to the planet named End?
Those 2 plot points was the sole reason Marsh journeyed to see the Emperox in book 1 and kicked off the entire series. I still do not know the answer. This book gets a 3/5 because it was at least an entertaining ride.