With The City & the City, China Miéville has created a fascinating, exciting story that takes a premise that could have come straight from a short story by Jorge Luis Borges and turns it into the kind of hardboiled detective story Borges would have loved. Tyador Borlú is a police detective in the European city of Beszel, a city that exists in the same space as another city, Ul Qoma. Beszel and Ul Qoma live in a very uneasy truce, with different governments, different cultures, and citizens who are trained to "unsee" anything in the other city. Moving from one city to the other is illegal, unless you go through special checkpoints with the proper visa and paperwork. If you move illegally—or even see something in the other city—you can get in trouble with a mysterious, powerful, extralegal organization called "Breach." So when a young woman is found dead in Beszel and it becomes clear she was actually murdered in Ul Qoma, Inspector Borlú immediately finds himself trying to navigate a labyrinth of bureaucracy, arcane laws and customs, and sinister conspiracy theories. The deeper he gets into the surreal investigation, the more he comes up against people and groups who will do anything to keep him from solving this mystery.
Miéville walks a fine line with this novel. It could easily become a loopy conspiracy thriller or an incomprehensible, metafictional mystery. But he keeps everything grounded in the grittiness of a police procedural and doesn't let the more fantastic elements overwhelm the story. Everyone in the story is weary, bitter and foul-mouthed, but also smart, tenacious and realistic. The novel has fantastic elements, but at it's heart, it's a shades-of-grey noir mystery. Personally, I tend to prefer my fantasy to be fantastic and my mysteries to be less gritty, but The City & the City is a great ride that kept me interested from start to finish.