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.
Peter Davison
as The Doctor
Sarah Sutton
as Nyssa
Janet Fielding
as Tegan Jovanka
Anthony Ainley
as The Master / Kalid
Nigel Stock
as Professor Hayter
Richard Easton
as Captain Stapley
Keith Drinkel
as Flight Engineer Scobie
Michael Cashman
as First Officer Bilton
John Flint
as Captain Urquhart
Judith Byfield
as Angela Clifford
Peter Dahlsen
as Horton
Brian McDermott
as Sheard
