Jon Pertwee

The Doctor

Caroline John

Liz Shaw

Nicholas Courtney

Brigadier Lethbridge-Stewart

Ronald Allen

Ralph Cornish

John Abineri

Carrington

Robert Cawdron

Taltalian

Michael Wisher

John Wakefield

Cheryl Molineaux

Miss Rutherford

Ray Armstrong

Grey

Robert Robertson

Collinson

Ric Felgate

Van Lyden / Alien Ambassador

Dallas Cavell

Quinlan

Bernard Martin

Control Room Assistant

John Moreno

Dobson

James Haswell

Corporal Champion

Michael Ferguson