Arriving at a human colony living in an artificial biosphere on Pluto, the Doctor discovers a citizen on the verge of committing suicide because of an impossible tax burden. Aiding the resistance, the Doctor discovers that the corrupt corporation controlling the colony is being run by an evil alien…
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Episode 1
The TARDIS arrives on Pluto which has been made habitable and
turned into a giant factory where the ruthless Company exploits its
under-paid workers.

Episode 2
The Doctor is taken prisoner by the Gatherer and sent to the
Correction Centre. Leela mounts a rescue attempt, but the Gatherer’s
men are waiting.

Episode 3
The Doctor is free but Leela has been captured by the Gatherer and is
sentenced to a grisly death by public steaming.

Episode 4
The Others launch a full-scale uprising against the Gatherer and his
Inner Retinue while the Doctor confronts the real head of the
Company.