Jon Pertwee

The Doctor

Caroline John

Liz Shaw / Section Leader Elizabeth Shaw

Nicholas Courtney

Brigadier Lethbridge-Stewart / Brigade Leader Lethbridge-Stewart

John Levene

Sergeant Benton / Platoon Under Leader Benton

Olaf Pooley

Professor Stahlman / Director Stahlman

Christopher Benjamin

Sir Keith Gold

Sheila Dunn

Petra Williams / Dr Petra Williams

Derek Newark

Greg Sutton

David Simeon

Private Latimer