The Culture's covert operations division, tasked with intervening in the affairs of other civilisations. SC recruits agents – both Culture citizens and outsiders – willing to do the morally ambiguous work that the Culture's utopian self-image prefers not to acknowledge.

A feudal, pre-industrial people living within the vast artificial structure of a Shellworld. The Sarl are unaware of the full extent of the universe beyond their level of the Shellworld, and their politics are characterised by dynastic intrigue and warfare.