Jon Pertwee as The Doctor

Katy Manning as Jo Grant

Nicholas Courtney as Brigadier Lethbridge-Stewart

Richard Franklin as Captain Mike Yates

John Levene as Sergeant Benton

Roger Delgado as The Master

Paul Grist as Bill Filer

Peter Bathurst as Chinn

Fernanda Marlowe as Corporal Bell

Donald Hewlett as George Hardiman

David Savile as Winser

Derek Ware as Pigbin Josh

Bernard Holley as Axon Man

Michael Walker as 1st Radio Operator

David March as 2nd Radio Operator

Patricia Gordino as Axon Woman

John Hicks as Axon Boy

Debbie Lee London as Axon Girl

Tim Pigott-Smith as Captain Harker

Kenneth Benda as The Minister

Royston Farrell as Technician