This book was every bit as good as the first in the series. They're long books that don't feel that long when you're reading them. It seemed like in no time flat I had knocked out 100-150 pages without quite realizing it.
Holden and the crew of the Roci are back in action, this time finding themselves leading the search for a missing child. The child came up missing shortly before an attack nearly destroyed her home, Ganymede. The alien protomolecule that destroyed Eros station in the first book is back in the form of the monster that attacked Ganymede. The protomolecule was supposed to have been marooned on Venus, so the question becomes, "How did it show up on Ganymede"? Also, is there a connection between the kidnapping of young Mei and the attack on her homeland? Not to mention, political tensions are running high, and the threat of a inter-planetary war looms on the horizon.
That's a sucky synopsis, but there's so much going on that it's hard to summarize without getting into spoiler territory.
Whereas in the first book, the story was told between the alternating viewpoints of Holden and Det. Miller, this time we not only see the story through Holden's eyes, but also Praxidike Meng (the father of the kidnapped child), Chrisjen Avasarala (a UN official from earth), and Seargent Roberta "Bobbie" Draper, member of the Martian Military and a survivor of the Ganymede attack. I found I really enjoyed the added viewpoints--especially Bobbie and Avasarala--as it really opened the story up more.
Note: Avasarala has already been introduced on the tv show. I'm hoping Bobbie will show up soon, too!