"The City & The City" is a novel by China Miéville that blends elements of fantasy and crime fiction. It is set in two fictional cities, Besźel and Ul Qoma, which occupy the same physical space but are perceived as separate entities by their inhabitants. The citizens of each city are trained to "unsee" the other, maintaining a delicate balance between the two. The story follows a detective named Tyador Borlú as he investigates a murder that crosses the boundaries of both cities. As he delves deeper into the case, he uncovers political tensions and the complexities of identity, ultimately challenging the nature of reality and perception in this unique setting.