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

Louis Mahoney as Newscaster

Roy Pattison as Draconian space pilot

Karol Hagar as Secretary

Harold Goldblatt as Professor Dale

Madhav Sharma as Patel

Dennis Bowen as Prison Governor

Richard Shaw as Cross

Luan Peters as Sheila

Caroline Hunt as Technician

Bill Wilde as Draconian captain

John Woodnutt as Draconian Emperor

Ian Frost as Draconian messenger

Clifford Elkin as Earth cruiser captain

Stephen Thorne as First Ogron

Michael Kilgarriff as Second Ogron

Rick Lester as Third Ogron

Ramsay Williams as Congressman Brook

Michael Wisher as Dalek (voice)

Stanley Price as Pilot

Laurence Harrington as Lunar guard