Air: April 10 1971. 6 eps.
The Time Lords have gotten wind of The Master’s schemes on the planet Uxarieus so they decide to let The Doctor stop him. The Doctor was still trying to fix the Tardis when it suddenly springs back to life. The Doctor takes Jo to an alien world she’s never seen before. There they find a feud between two worker factions, one of them is being used by The Master to uncover a doomsday weapon. Can The Doctor prevent him from reaching the most dangerous weapon in the Universe?