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.
Released: May 02, 1970
Runtime: 175 minutes
Genre: Science Fiction, Drama, Adventure
Stars: Jon Pertwee, Caroline John, Nicholas Courtney, Ronald Allen, John Abineri, Robert Cawdron
Crew: Michael Ferguson (Director), David Whitaker (Writer), Barry Letts (Producer), Dudley Simpson (Music)