Where can I watch “Space: 1999” Season 2 Episode 23 online?

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Watching earlier episodes in season 2 helps you follow the plot and character arcs leading into this episode.

Watch Space: 1999 Season 2 Episode 23 Online

“The Immunity Syndrome” — Watch "Space: 1999" Season 2 Episode 23 online in HD for free. Check streaming providers, cast, and episode details.

Oct 29, 1977 Season 2 Episode 23 51 min PG

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Space: 1999 Season 2

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Season 2 Episode 23 — Aired on Oct 29, 1977 • runs about 51 minutes.

Directed by Bob Brooks.

Written by Johnny Byrne.

Notable cast/guest names in this episode include Martin Landau, Barbara Bain, Catherine Schell, Tony Anholt.

This page includes 1 official still(s) (when available) plus legal availability links.

Looking for “watch Space: 1999 Season 2 Episode 23 online”? This is a legal-only guide with synopsis, stills, and navigation for this season.

Synopsis

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.