A world divided into a dark and light side. The Stargate resides on the dark side of the planet where the "Touched" exist. The light side is inhabited by the "Untouched." A histaminalytic virus is present on the planet, causing anyone with histamine in their bodies to succumb to primeval tendencies.
The leader of the light side is Tuplo.
The Broca Divide - SG-1 journeys to the land of the light, and helps save a large portion of their population from a parasitic infection.
Enigma - Tuplo invites a group of Tollan refugees to live in the Land of Light, but they refuse because the people are too primitive.
Family - Teal'c's wife and son go to live in the Land of Light, safe from Apophis's influence.