Emissaries From The Dead
The Diplomatic Corps is part of the government of an interstellar Commonwealth. This is not your father's Star Trek future. Humanity is if anything more fractious than today, even in the face of meeting many other intelligent alien races as it moves out into the galaxy. One such race is the AISource, a collective of sentient software agents that gains new members as they outlive their programmers. They built One One One, a huge cylindrical habitat, and populated it with several engineered species. One of the species is the Brachiators, an intelligent sloth-like race that lives in the Uppergrowth, a forest at the central hub. A group of scientists from the Diplomatic Corps is onsite to do field studies of the Brachiators, and one of their number has been murdered. Enter Andrea Cort. She's a Dip Corps investigator, who considers herself a monster, as do many others, for a childhood atrocity.
This novel starts out very bleak. In fact, I almost quit reading it more than once during the first half of the story, because life is too short and there are too many books I really want to read to stick with something that's just depressing. I stayed with it, though, because Adam-Troy Castro's writing flows smoothly, and before I knew it, I was well and truly sucked into the story.
The murder mystery at the heart of the story is not really that surprising; I correctly anticipated several twists in the tale, and that's not usual for me. However, I got almost the feeling that I used to when I watched Columbo as a kid, where we the audience knew who committed the murder, but the pleasure was watching Peter Falk's Lt. Columbo figure it out. I say almost that feeling, because we don't know who the murderer is until Andrea Cort figures it out. And that feeling is pure pleasure.
It was also a particular pleasure to catch resonances to quite a few other science fiction novels I've read over the years: One One One is Arthur C. Clark's Rama writ large; the AISource is the very sort of pervasive artificial intelligence as the TechnoCore from Dan Simmon's Hyperion; the character of Andrea Cort strongly resembles Paula Myo from Peter F. Hamilton's continuing Intersolar Commonwealth series; and the way that Andrea Cort unravels and reveals not one but a half-dozen intertwined mysteries, so that we're forced to reconsider everything we thought we knew about the setting and characters again and again, is like the heart of Orson Scott Card's Speaker for the Dead.
This is a heady brew of a book, with the richest portion being the positive growth that is imposed on Andrea Cort. Yes, imposed on her.
Outside of Doctorow's Little Brother, I consider this the finest science fiction novel of 2008, and I cannot recommend it highly enough.