The Idle Reflection
Episode 59
Air Date 12/27/1979 
Episode guide
The Footsteps of Footstep Village
Planet of a Pint-Size Room (Part 1)
There is a planet that, centuries ago, was so much like the Earth that people at the time called it the Earth's mirror image in Andromeda. Its history took a different turn when, unlike on Earth, the flesh-and-blood humans there managed to remain the masters of their world. What happened next is something that the inhabitants of the Seven Galaxies do not like to talk about...