Jon Pertwee

The Doctor

Katy Manning

Jo Grant

Nicholas Courtney

Brigadier Lethbridge-Stewart

Richard Franklin

Captain Mike Yates

John Levene

Sergeant Benton

Roger Delgado

The Master

Pik-Sen Lim

Captain Chin Lee

Raymond Westwell

Prison Governor

Michael Sheard

Dr. Roland Summers

Simon Lack

Professor Kettering

Fernanda Marlowe

Corporal Bell

Neil McCarthy

George Patrick Barnham

Clive Scott

Arthur Linwood

Roy Purcell

Chief Prison Officer Powers

Eric Mason

Senior Prison Officer Green

Bill Matthews

Prison Officer

Barry Wade

Prison Officer

Dave Carter

Prison Officer

Martin Gordon

Prison Officer

William Marlowe

Mailer

Hayden Jones

Vosper

Kristopher Kum

Fu Peng

Tommy Duggan

Senator Alcott

David Calderisi

Charlie

Patrick Godfrey

Major Cosworth

Johnny Barrs

Fuller

Matthew Walters

Main Gates Prisoner

Timothy Combe

Prisoner (uncredited)