Parts: 4
Writer: Ian Stuart Black
Airdates: 11 March 1967 - 1 April 1967
Production Code: JJ

Doctor: second
Companions: Ben, Polly, Jamie

Creature Feature: Macra

Story: The TARDIS crew arrive at an Earth colony in the far future, where all the residents are happy to serve under their Pilot. The atmosphere of gaiety is reinforced by the colony's holiday-camp-like structure, with lots of entertainment and pampering - which Ben and Polly cannot resist enjoying, though the Doctor and Jamie are less enthusiastic.

But the colony is not as perfect and carefree as it looks. No sooner has the TARDIS arrived than Jamie is attacked by a colonist on the run - Medok, whose tales of insect-like creatures that emerge at night have targetted him for rehabilitation by the officers, who do not allow such rumors to spread. The Doctor is intrigued, suspecting that there may well be truth to Medok's words, so he risks the wrath of the colony's leaders to help Medok and learn what he has to tell.

The Doctor soon learns that Medok's tales are true - attempting to evade security by hiding in a construction area at night, he and Medok come face-to-face with one of the hideous Macra. But the leaders of the colony still refuse to believe in their existence, and soon the Doctor and his companions find themselves under constant watch and laboring in the planet's deadly gas mines - except for Ben, who has fallen under the colony's spell...