- You may wish to consult
Planet Xfor other, similarly-named pages.
Planet X was the most boring planet in an alternate universe. It was named Planet X because it was too boring to give the planet a name. The Doctor found the planet so tedious he didn't want to arrive on the planet in the first place, and when he arrived with Bernice Summerfield he instantly wanted to leave even if his TARDIS was too heavily damaged and worn out to take off again.
It was a human colony. During the Great War, the planet's government decided to make their colony so boring that nobody in the conflict would be interested in going to the planet. The plan worked and Planet X was the only planet to be unaffected by the Great War.