Original air dates 30 October 1976 – 20 November 1976. First adventure without a companion.
Doctor leaves a note. Warns them of the danger. Doctor is a specific type of Time Lord. His TARDIS is moved to a museum. Security works on catching him, he hides in plain sight and goes to the Panopticon.
The Doctor goes to stop the gunman, finds the gun and apparently shoots the President before he can speak. Credits roll.
It’s a whodunit with the Doctor in the hotseat. Politics abounds.
Doctor chases the Master into a brain storage machine on Galifrey. It is a nightmare domain controlled by the Master, who traps the Doctor to kill him. Repeatedly. Credits roll.
More illusions try to claim the Doctor. He disbelives. The Master chortles. Doctor is chased around, gets his opponent to shoot at him from swamp gas, which blows up. Doctor fights him off, but gets caught and is being drowned when credits roll.
Doctor finds Goth, gets the story from the dying Time Lord. The Time Lords don’t like the story and will fix truth to make them more reliable.
The Master’s body is to be burned, and then used as the scapegoat. The Master still lives, and steals the ancient key and rod to get to the Eye of Harmony which can make something eternal.
The Master is happy to destroy Galifrey to get infinite power and starts that process, while the Doctor chases him past styrofoam rocks and shaky can.
Day is saved, Master may have died, Doctor is shooed off Galifrey and the Time Lords are left to clean up thier mess.