Title: Perdido Street Station
Author: China Miéville
Content Rating: R for language, sex, and the sucking of brains
Beneath the ribs of a dead, ancient beast lies New Crobuzon, a squalid city where humans, arcane races, and bio-engineered Re-mades live in perpetual fear of Parliament and its brutal militia. Everyone's got something to hide, including Isaac -- a brilliant scientist who's in over his head. He's been hired to help a de-winged birdman fly again, but that's not the problem. The problem is one of the specimens he collected for his research: a caterpillar that feeds only on a hallucinogenic drug. What finally emerges from the cocoon turns out to be so terrible, not even the Ambassador of Hell will aid in its capture.
The world in this book is AMAZING. It felt like a dark, more-serious version of Terry Pratchett's Discworld. It's got everything: steampunk tech, psuedo-scientific magic, fantastic sentient species, monstrous terrors, mafiosos, oppressive governments, even artificial intelligence.
The writing is really good, if you don't mind the tangents into a description of some new burrough of New Crobuzon (which really aren't tangents, as the city is one of the main characters in the book, but some might not see it that way). The plot, too, was really strong. I admit there were moments I felt were too coincidental (like when Isaac learned what to feed the caterpillar), but it led me along nicely. And especially once the cocoon hatched, I couldn't put the book down.
Assuming the content doesn't freak you out, you should totally read this book.