The Disappeared, by Kristine Kathryn Rusch, is the first book in her Retrieval Artist series; that said, it is actually the second book in the series that I have read, the first (Buried Deep) having been picked up on a whim at a used book store.

The Disappeared is a far future science fiction novel that is focused on character and ethics ahead of hard science or ideas. In fact, if you ignore the setting, at its heart this novel is one part mystery, one part crime drama, and one part moral quandary. Like many sci fi works, however, the setting serves as a backdrop for a thought experiment.

The future that Rusch portrays is one where humanity has burst onto the interstellar scene, made contact with a number of alien races, and commenced political and commercial relations with them. As a necessary part of this interspecies relationship, some give and take is politically required, and this discourse anchors all of the problems that the character's in Rusch's world face.

The main characters, Miles Flint and Nolle DeRicci, are detectives in the Armstrong Dome (on the moon) and throughout the novel are tasked with mitigating three separate alien-human disagreements that arise. The sticking point is justice: a key aspect of the galaxy that Rush has crafted is that the governments of the various starfaring species have agreements in place that allow them to extradite members of other races who have been found guilty of a crime in their own society. This may sound innocent on the surface, but extremely tough moral dilemmas arise when trying to rationalize the vastly different nature of criminal acts in alien societies, as well as the different forms of punishments that each metes out, with normal human sensibilities and ideals.

The novel unfolds primarily through the eyes of the main characters, but also occasionally jumps to different individuals in order to provide context. Rusch's prose is solid throughout, and she does an extremely good job of making the moral quandaries difficult to digest, and fantastically uncomfortable.

If you are looking for some space cop fiction that will make you think, then I heartily recommend The Disappeared.