Katy Manning

At a crucial Peace Conference, Sir Reginald Styles, the diplomat with the best chance of averting a war between the Chinese and Russians is almost assassinated by a mysterious guerrilla.The fighter then disappears with Jo and the Doctor - into a terrifying future Earth ruled by the Daleks and their brutish slaves, the Ogrons.

A full scale riot takes place at Stangmoor Prison and Jo is taken hostage.

The Doctor and Jo land on a spaceship in the far future as it is attacked by Ogrons, which the human crew see as Draconians. The Doctor and Jo are taken to Earth as spies.

The mind parasite within the Keller Machine becomes too powerful for the Master to control. It learns how to move of its own accord and goes on the hunt for new minds.

The Master is behind the Keller Machine and uses it to recruit the rioting inmates at Stangmoor Prison. He plans to capture a missile and fire it at the World Peace Conference.