The Doctor returns to Gallifrey, claims his rights and is inaugurated President. It soon turns out that he has led a group of aliens called Vardans to the planet to eradicate them completely. After they are destroyed, the Sontarans take their opportunity and follow them in their invasion until they are destroyed by the Doctor.

Mysterious forces are at work in 1930s Tibet. The once gentle Yeti have turned savage and besieged a Buddhist monastery. The Second Doctor, Jamie and Victoria arrive expecting a friendly welcome from the abbot, but soon become ensnared in the plans of the extradimensional being known as the Great Intelligence.

A factory's workforce is dwindling as divisions between the workers and management widen.

It is the mid-1980s. The economy has not improved. For 17 years Professor Frank Merrick has been ensconced in a research lab of a provincial university working on a cure for the common cold. He is very near success. Can he avoid becoming yet another victim of the eternal cutbacks?

17 year old Kevin discovers that his sick father, Whistling Wally, is dying.

The positronic brain of robot RB-34 (Herbie) has an unforeseen 'extra': he can read human thoughts. So his take on the First Law of Robotics is unorthodox: he tells human beings only what he believes will not hurt their feelings. Can renowned robopsychologist Dr. Susan Calvin 'fix' RB-34? Or are there areas of her own psyche where she would rather not hear the truth?

The small East Anglian village of Plampton has one distinction - a famous unsolved murder. A cynical journalist decides to go there to see what he can stir up. But Plampton is a community linked by telepathy and led by a witch.