In the 26th century, the Doctor and Jo uncover a plot by the Master to provoke an interplanetary war between Earth and Draconia.
Jon Pertwee
as The Doctor
Katy Manning
as Jo Grant
Roger Delgado
as The Master
Vera Fusek
as President of Earth
Michael Hawkins
as General Williams
Peter Birrel
as Draconian Prince
Lawrence Davidson
as Draconian First Secretary (uncredited)
Timothy Craven
as Cell guard (uncredited)
Ray Lonnen
as Gardiner
Barry Ashton
as Kemp
John Rees
as Hardy
James Culliford
as Stewart
