The Line of Polity is a 2003 science fiction novel by Neal Asher. It is the second novel in the Gridlinked sequence. In this novel, Earth Central Security (ECS) agent Ian Cormac is placed at the center of a civil war on the planet Masada, where an elite Theocracy lives in cylindric habitats in orbit and violently rules over commoners enslaved to laborious agriculture jobs on the planet's surface.