This book starts poorly, and isn’t as interesting as the previous one in the series (Isaac Asimov’s Robot City: Robots and Aliens: Changeling). The introduction uses an alien species with spending any time to describe them, and the process of trying to infer what they are and how they operate distracts from the overall plot. Its a little bit like a William Gibson book, but a more clumsy attempt at it which makes the first couple of chapters hard to comprehend.
Worse than that, this book spends a lot of time dwelling on physics details (the author is a physicist), and Ariel seems obsessed with a desire for recognition and power that doesn’t exist in the previous books. A lot of the book is also about her love affair for Derec and a robot, which is out of place with the rest of the series as well. In the other books the romantic relationship between Derec and Ariel is a minor plot element, not something which has many pages devoted to it, and I think that fitted better with the overall plot.