End of Eternity (Space: 1999)

Lore & Background

The episode opens with an Eagle crew surveying a passing asteroid. They discover an underground cavity with breathable air and blast open an outer hatch. Inside, they find a male humanoid seriously wounded; he is taken to Moonbase Alpha but declared dead. The alien mysteriously revives, showing incredible cell regeneration. Professor Bergman discovers the asteroid itself can regenerate after being destroyed by antimatter. The alien, calling himself Balor, claims to be a scientist from Progron whose people achieved immortality but became corrupt. He says he was imprisoned for trying to reverse the experiments. Koenig suspects Balor is lying. Balor uses psychic powers to kill pilot Mike Baxter and later reveals he is a psychopathic tyrant who intends to dominate the Alphans. The crew lures Balor into an airlock and ejects him into space. They destroy the asteroid, but it rematerializes.

Reader's Guide

The episode was filmed at Pinewood Studios in October 1974. It was disliked by writer Johnny Byrne, who felt the plot was too claustrophobic and the villain one-dimensional. However, it received largely positive reviews from critics, with some calling it one of the series' best episodes. Peter Bowles' performance as Balor divided opinion: some found him miscast, while others praised his role as memorable and enjoyably devilish. The episode explores themes of immortality and the value of death, echoing earlier episodes. The scene of Baxter's assault on Koenig was cut before transmission to remove explicit violence. The incidental music used library tracks by composers including Robert Farnon, Roger Roger, and David Snell.

Did You Know?

• The episode was filmed over 12 days between 9 and 28 October 1974.
• Johnny Byrne named the villain Balor after an evil god in Irish mythology and the Phoenician deity Baal.
• The scene of Balor's escape from Medical was filmed on 21 October 1974.
• The episode first aired in the United States on 15 November 1975, before its UK broadcast on 20 November 1975.