Embassytown is Miéville channeling Ursula K. Le Guin with a strange piece of linguistic scifi that builds a fantastic world, but then fails to do much with it.

Welcome to Embassytown, a small town on the edge of human space. The locals, the Ariekei, are masters of exotic biotechnology, and speak a language unique in the universe. The Ariekei tongue, Language, is non-symbolic. Statements in Language simply are, voiced by two mouths simultaneous. The Ariekei themselves cannot communicate with machines or single humans, only with carefully groomed pairs named Ambassadors who they can recognize as minds.

Avice, our narrator, is a small-town girl who becomes part of an Ariekei simile, a living part of speech. She escapes Embassytown as a sailor on the dimension-skipping immerships, but returns when she marries a graduate student in linguistic. He is fascinated by the Language, and they way that it is impossible for Ariekei to lie. But he becomes distant, constructing a theology where the truthful Ariekei are angels, and the rest of the galaxy fallen.

When a new Ambassador arrives, and their discordant speech has a narcotic effect on the locals, things begin to move very quickly towards collapse. The Ariekei become a civilization of addicts, colonial patterns reinscribe themselves, and then the delicate biotech that keeps everyone alive begins to collapse. One faction of Ariekei cut off their "ears", becoming an army of the communication-less Deaf with a plan to wipe out humans and their verbal drug, and let the next generation rebuild free. Avice and her allies must teach a minority to use Language in a conventional way, to speak symbolically and lie.

The setting is incredible, but the plot and characters just... exist. I get the sense that Miéville wanted to use a lot of abstruse linguistic terminology, but he doesn't get it well enough to explain why Language is truly uncanny as opposed to merely odd. Still, lots of points for inventiveness.