This is book number 3 in the Foreigner Sequence 4 series.
In the wake of civil war, Bren Cameron, the brilliant human diplomat of the alien atevi civilization, has left the capital and sought refuge at his country estate, Najida. But now he is trapped inside Najida-which has been surrounded by enemies- with the powerful grandmother of his ally, Tabiniaiji, atevi leader of the Western Association. Ilisidi, the aiji-dowager, is not inclined to be passive and sends Bren into enemy territory, to the palace of the leader of the rebels.
Bren's mission is to negotiate with Machigi-a young atevi lord who has never actually seen a human-and somehow persuade him to cease his hostile actions against the west. Is Bren a shrewd enough negotiator to stay alive, and not alienate Ilisidi or Tabini, while also representing the interests of their enemy?