The inhabitants of the planet Karfel are suffering under the tyrannical rule of their leader, the Borad, who has brought his world to the brink of interplanetary war. Those who dare to oppose the will of the Borad are mercilessly sacrificed to the Timelash, a fate considered by many to worse than death. When the Doctor arrives of Karfel he soon discovers the Borad's horrifying plan, a plan which will directly affect his young American assistant, Peri.