Dulkis was an isolated planet which orbited a minor, yellow star near the edge of a spiral galaxy.

This spiral galaxy may have been one of the Ten Galaxies that the Dominators said they ruled.

Dulkis was hot, dry and ochre in colour from space. It had few valuable minerals, but there were some materials that could be used for nuclear fission in the northern hemisphere. Dulkis was the home world of the Dulcians. One of the locations on the planet was the Island of Death, a dry, rocky island in the southern hemisphere used by the Dulcians for testing nuclear weapons. It was later chosen as the landing site by the Dominators, who wanted to use the radiation and the thin crust in the area. (TV: The Dominators)