Cetaganda - Lois McMaster Bujold

The dowager Empress of Cetaganda has died, and Miles is sent to the Imperial funeral to represent Barrayar, along with his cousin Ivan, and a small contingent of minders. Some eighty years earlier Cetaganda unsuccessfully tried to invade Barrayar, and an uneasy truce still lies between the two planets. Cetaganda is a rigidly hierarchical society composed of three tiers - the Haut lords and ladies (the latter travel in opaque bubbles and are rarely seen by off-worlders), preoccupied with creating and displaying beauty and with genetic engineering in the quest for the perfect human, are served by the ba, a genderless servant class who are also used to try out new genetic modifications, and defended by the warrior Ghem-lords who, if they're particularly outstanding, may be rewarded with a Ghem wife. When the body of a ba is found in front of the Empress's body, Miles becomes involved in a mystery which, once revealed, could critically destabilise Cetagandan society.
The descriptions of Cetagandan art, mores, etiquette and technology are a hallmark of McMaster's writing - unique, fully realised and internally coherent, even her minor characters are individualised and well developed, and glimpses of humour twinkle throughout: when asked how his egalitarian Betan mother managed to adapt to aristocratic Barrayan culture she married in to, Miles answers "No problem. She says egalitarians adjust to aristocracies just fine, as long as they get to be the aristocrats." So true.
Perhaps the reason this series retains its energy, enthusiasm and interest throughout (unlike many other series, particulalry in the genre) is that McMaster has written them out of order, picking whatever aspect of Miles' life she feels like at the time. Cetaganda was written after the next book, Ethan of Athos, and answers some of the questions chronoligical readers might have about the Cetagandan culture. Whatever the reason - and I'm reluctant to ponder it too deeply, for fear that discovering the why will, like a magician's trick, diminish my enjoyment of the experience - none of McMaster's works are disappointing on subsequent encounters, and I have to force myself to continue at a leisurely, restrained pace. - Alex