Planet (The Experimenters)

An Earth-like planet was home to a humanoid race who were called "the Master Race". They captured the First Doctor, John and Gillian when they arrived on their planet and took them to a prison compound. The planet's government decided to use the prisoners as test subjects in their experimental space vehicles. The Doctor and his grandchildren were placed in a rocket, but took control of it and dropped explosive fuel containers on the testing grounds, destroying it. (COMIC: Experimenters]]'')