The story is a fairly typical crime story: a woman's body is found and Inspector Borlu has to solve the murder. But the setting is what makes the story something more. The woman's body is found in Beszel but she was most recently working and living in Ul Qoma. These two cities actually exist in the same physical location but due to a schism that has yet to be explained, the two places don't interact. Not only do they not interact, they're not allowed to interact. Even if your neighbor's house is an arm's length away from you, if your neighbor lives in Ul Qoma and you live in Beszel you have to "unsee" their house. If you failed to unsee, you will have breached, which means a committee that is above the laws of either Beszel or Ul Qoma will come and deal with you and you will not be heard from again. Here's Borlu explaining some of the (very little) leniency with Breach.
"If I or one of my friends were to have a moments failure of unseeing (and who did not do that? who failed to fail to see, sometimes?), so long as it was not flaunted or indulged in, we should not be in danger. If you were to glance a second or two on some attractive passerby in Ul Qoma, if I were to silently enjoy the skyline of the two cities together, be irritated by the noise of an Ul Qoman train, I would not be taken." (64)The two cities inhabit the same physical space but they must live in different worlds. The people do acknowledge that the places are sharing the same space but to claim that the two cities are one in the same is blasphemy. The citizens have a word for same physical space but vastly different places: grosstopical.
These two cities don't exist on some foreign land or even distance future where all countries are like this. The girl that was found murdered is from the US, studying in Canada and attending her universities campus within Ul Qoma to work on her archaeology PhD. They don't go into much detail about how other countries view the cities unique position but, from the standpoint of the locals, it is certainly tolerated. The girl and others who wish to visit either Beszel or Ul Qoma must take a 2 week long intensive course so they can learn to unsee the other city-state before they are issued a visa. Tourists have to learn to not only unsee foreign buildings that are right in front of them, but also unsee foreign people who are sharing the same sidewalk as them. You cannot notice them but you also can't walk through people as if they aren't there. You have to avoid them without noticing them or be guilty of Breach. (If you notice them, Breach! If you do such a good job of not seeing them that you run into them, Breach!) Borlu describes an incident from his childhood, when Breach showed up after an Ul Qoma van skidded on Ul Qoma streets and hit a Beszel vehicle.
In seconds, the Breach came. Shapes, figures, some of whom perhaps had been there but who nonetheless seemed to coalesce from spaces between the smoke of the accident, moving too fast it seemed to be clearly seen, moving with authority and power so absolute that within seconds they can controlled, contained the area of intrusion. (81)It takes a little while to learn all of the rules for the cities. At no point does the narrator give all of the information to the reader. You get clues that something isn't quite right for awhile until finally the details fall into place. The problem with this is I had trouble focusing on the text, which was very clearly avoiding the details. In World War Z the reader doesn't get all of the details because it's clear that everyone is already familiar with the details and this style works. You're given enough to follow what's going on while enough is held back that it a) feels real and b) lets you fill in some of the details yourself to make it even scarier. The City & The City isn't a horror story so there is no reason for the reader to fill in the unknowns to make it scarier and the missing details are confusing. My friend that recommended the book to me had tried to explain the dopplurbanology (as it is called in the book) but it is hard to explain. I'm not sure if already having an idea about the 2 cities made the beginning more confusing or not but now that more of the rules are explained the narrative flows better.
As it stands I am more interested in the 2 cities than I am in the murder, now that I have more information and can follow the setting better. So far the cities have served only as an interesting setting but I'm hoping the schism will be examined and will end up being more than just a trick.
Title quote from page 113