The Doctor

Tom Baker

Acting

Sarah Jane Smith

Elisabeth Sladen

Acting

Harrison Chase

Tony Beckley

Acting

Richard Dunbar

Kenneth Gilbert

Acting

Sir Colin Thackeray

Michael Barrington

Acting

Amelia Ducat

Sylvia Coleridge

Acting

Scorby

John Challis

Acting

Arnold Keeler / Krynoid (voice)

Mark Jones

Acting

Hargreaves

Seymour Green

Acting

Derek Moberley

Michael McStay

Acting

John Stevensen

Hubert Rees

Acting

Charles Winlett

John Gleeson

Acting

Doctor Chester

Ian Fairbairn

Acting

Major Beresford

John Acheson

Acting

Sergeant Henderson

Ray Barron

Acting

Chauffeur

Alan Chuntz

Acting

Guard Leader

David Masterman

Acting

Guard

Harry Fielder

Acting

Guard

Pat Gorman

Acting

Guard

Ian Elliott

Acting

Sir Colin's Aide

Keith Ashley

Acting

Marine

Ronald Gough

Acting

Marine

Patrick Milner

Acting

UNIT Soldier

Barry Summerford

Acting

UNIT Soldier

Tony Snell

Acting

UNIT Soldier

Patrick Ginter

Acting

UNIT Soldier

Rowland Geall

Acting

UNIT Soldier

Derek Wayland

Acting

The Krynoid

Keith Ashley

Acting

The Krynoid

Ronald Gough

Acting