When the Tardis runs low on Zeiton-7 the Doctor must visit the planet Varos, a mining colony ruled by a brutal regime that encourages public torture and executions.
The Doctor and Peri must escape the Punishment Dome, a sadistic system of entertainment and political control on Varos.
The governor of Varos begins to suspect someone is working against him. The alien Sil puts his plans into motion.
The governor faces the punishment dome alongside Peri whilst the Doctor fights to stop the evil alien Sil.
