Overview

Astronauts rescued from a mission to mars are kidnapped when they arrive back on earth. They seem to have been irradiated, and can now kill people merely by touching them. But the Doctor discovers the astronauts have been replaced with Alien ambassadors who are being forced to behave in a hostile manner. With The Doctor traveling to the alien mother ship, and Liz kidnapped, The Brigadier is left wondering who to trust.

Top Cast

Jon Pertwee

The Doctor

Caroline John

Liz Shaw

Nicholas Courtney

Brigadier Lethbridge-Stewart

Ronald Allen

Ralph Cornish

John Abineri

Carrington

R

Robert Cawdron

Taltalian

Michael Wisher

John Wakefield

C

Cheryl Molineaux

Miss Rutherford

R

Ray Armstrong

Grey

R

Robert Robertson

Collinson

R

Ric Felgate

Van Lyden / Alien Ambassador

D

Dallas Cavell

Quinlan