Tales of life under the 'bloody sun' of Darkover, a lost human colony, reverted to feudalism, where some humans have interbred with the natives to produce the Comyn, a psi-caste of rulers. The series ranges right from the original Landfall, through the Ages of Chaos where the new psi powers lead to devastating wars, through to the crisis of recontact with mainstream, relatively alien, Terrans.
The early books in the series are okay romps (and are probably half a point lower than the overall series rating), but in 1975 with Heritage of Hastur something changed, and they improved, and deepened, dramatically (and most of these are probably half a point higher than the overall series rating). The focus of plots varies widely throughout the series, but they are known for dealing sensitively with the intense intimacy between husband and wife brought by psi-contact, with homosexual relations, both male and female, with the place of women in a feudal society, with the use and abuse of power, with culture shock.
