A fun, clever and satisfying "mystery science fiction" read. The world is a bit futuristic, yet Old World, as it's set in various European cities. The writing is part Agatha Christie and part Camus. The science leans more toward philosophy and math, as well as a little bit outer space. While there isn't a real focus on character development, many of the characters are quite amusing and distinctive.

Nelly Dean!! Surprise awesome character/narrator. I've heard this book takes a turn midway, but so far this is just pure storytelling goodness.