Space: 1999 - Season 2 - Eps 23: The Immunity Syndrome
The arrival of the Alphans on another planet seems to cause a change in its atmosphere, setting off pollution and poisoning of the water. They meet Zoran, the sole survivor of the last exploratory force, who tells them that the planet is controlled by an immortal being - with whom Koenig must parley if he and his crew are to leave the planet alive.
About Space: 1999

Title: Space: 1999
First Air Date: 1975-09-04
Last Air Date: 1977-11-12
Status: Ended
Rating: 7.1/10 (from 140 votes)
Language: EN
Seasons: 3
Total Episodes: 48
Network: ITV1
Genres: Sci-Fi & Fantasy
Production Companies: Group 3, RAI, ITC Entertainment, RAI Cinema
Synopsis
The crew of Moonbase Alpha must struggle to survive when a massive explosion throws the Moon from orbit into deep space.
Cast

Martin Landau
John Koenig

Barbara Bain
Helena Russell

Catherine Schell
Maya

Tony Anholt
Tony Verdeschi