The DOctor has a double: Salamander, inventor of the 'sun-store', who has saved the world from starvation. Giles Kent, once Salamander's ally, suspects his real aim is to seize power. The Doctor falls in with Kent, while Jamie and Victoria are given jobs in Salamander's retinue. After a volcanic eruption in Hungary, political leader Denes accuses Salamander of creating the disaster himself, but Salamander responds by having him deposed and arrested ...