Underworld, Part Two

Résumé :

Crashing inside a newly formed planet, the Doctor and others find it inhabited by a slave labor mining society, where rocks are harvested for their radioactive energy and human life has little value. With a population controlled by deliberate cave-ins, poison gas, and periodic sacrifices to an Oracle, the miners, called Trogs, are also descendants from Minyos, and who desperately desire freedom.