Terrance Dicks

The Time Lords have a mission for the Doctor. Together with Sarah and Harry, he finds himself stranded on the war-torn planet Skaro where the conflict between the Thals and the Kaleds has been raging for a thousand years. Chemical and biological weapons have started a cycle of mutation among the planet's inhabitants that cannot be stopped. But Kaled scientist Davros has perfected a life support system and travel machine for the creature he knows his...