The TARDIS has stalled in mid-flight, and it is only on the planet Varos that the Doctor can find the precious Zeiton-7 ore he needs to continue his travels through time and space. Arriving on the planet, he saves the rebel Jondar from execution, and incurs the wrath of Sil, the sadistic representative of the Galatron Mining Corporation on Varos. The hunt is on for the Doctor and his rebel friends. And as they are pursued through the corridors of the deadly Punishment Dome, the Doctor discovers that the people of Varos have some very disturbing ideas of entertainment...