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

Derek Ware

Private Wyatt

Walter Randall

Harry Slocum

Ian Fairbairn

Bromley

Roy Scammell

RSF Sentry

Keith James

Patterson

Peter Thompson

Primord

Philip Ryan

Primord

Walter Henry

Primord

Pat Gorman

Primord

Dave Carter

Primord

Barry Letts

Loudspeaker Voice

Derek Martin

UNIT Soldier

Terry Walsh

UNIT Soldier

Ian Elliott

UNIT Soldier

Alan Chuntz

UNIT Soldier

Alan Clements

Technician Phillips