While investigating a vanishing Concorde at Heathrow Airport, the Doctor and his companions are thrown millions of years back in time, when a mysterious alien called Kalid is trying to control the ancient powers of the Xeraphin.
The Doctor
Nyssa
Tegan Jovanka
The Master / Kalid
Professor Hayter
Captain Stapley
Flight Engineer Scobie
First Officer Bilton
Captain Urquhart
Angela Clifford
Horton
Sheard
Andrews
Adric
Anithon
Zarak
Melkur
