The quick and dirty:
Rating: 2 stars
Length: Long in a distinctly clunky way (465 pages)
Publication: August 5, 2008 from Daw Books
Premise: The planet of Harmony is supposed to exist in a balanced seven-caste system, but the system is starting to waver. The planet is venting its displeasure with disasters like earthquakes and storms, the old High Priestess died when the Temple collapsed, and her successor is Sissy, a common Worker girl who has been hiding her unusual marks of all seven castes for years. Jake, a spy from the Confederated Star System, was sent to Harmony to steal a secret that could help humanity win its war with the Maril. When the two are thrown together, change starts to sweep the planet with the force of an earthquake.
Warnings: Assassination of children and families, imprisonment and mistreatment in asylums
Recommendation: Give this one a miss. Blending science fiction and fantasy elements in a single setting is difficult, and Bentley hits a halfway point that misses the best elements of both.