This book is a really interesting mix of concepts. I found myself talking about it to someone just yesterday, and realized it is still intriguing me.
The book is told in the first person, in the form of a narrative by the main character, Ae, to a stone. We find out why the stone is so important as the story progresses.
Ae is in prison, the only criminal in the massive t'T interplanetary system, and he/she tells the story of how she came to be there to her stone companion. Interestingly, I stumbled across a number of reviews for this book, and found most referred to Ae as a he. And it is true, Ae seems to be more masculine, and I was never sure if that was on purpose, or whether the author slipped into his own natural style because it was first person. The reason for the confusion is that Ae switches sexes.
The people (humans) of the t'T have nanoTech in their bodies, sub-atomic AI nanorobots (much like the scenario in Iain M. Banks's THE CULTURE series), which extend their lives, keep them free of disease, and give them the ability to change the way they look, including the most bizarre of apendages, as well as change sex. Ae started out as a woman, changed to a man, but by the time she is in prison for the first time (she's a serial killer, and the only known killer, or even criminal, in the whole of the t'T), she's stripped of her nanoTech, and she begins to revert to her original female state in prison. As a result, I thought of her as *she*, but obviously a lot of people thought of her as *he*.
Ae's prison is in the centre of a star. The good citizens of t'T want to make sure she/he stays put and will never darken their doors again, but Ae starts hearing a voice in her head. One that offers escape if she will be a contracted assassin for the people the voice represents. The job? Kill all the people on a certain planet, while leaving the planet intact. All 60 million people have to die, or Ae goes straight back to jail.
Willing to do anything to get out of jail and get her nanoTech back (she doesn't feel human without it), Ae is sprung from the seemingly inescapable jail, and hums and haas about her mission for a while, running from planet to planet to keep a step ahead of her jailers (there aren't any actual police, as they didn't think there WERE criminals anymore until Ae came along).
But eventually, Ae faces up to her promises and sets out to complete her mission, all the time speculating on who her employers are. Roberts brings very interesting and complex science into his plot, using quantum physics as the lynchpin on which his story hangs.
I simply had to know who wanted the whole planet dead, and wasn't let down when I found out whodunnit at all. It was an interesting, unusual read, and I'll definitely look out for more of this author's work.