The One With… a space sci-fi story within a middle ages fantasy story.
After escaping Magnus, the Doctor and Peri land in medieval England to see a peasant named Gurth being hunted by the mythical Herne the Hunter. When they reach the village, they discover that nobody lives to old age there. When their Time comes, they're taken away and never seen again. And anyone who tries to escape, then Herne comes for them... The Doctor and Peri join up with some rebels, and try to find out just why the Baron imposes this culling, the secret of the Zeron and just who are the Sentinels of the New Dawn?
The original script was written by Brian Finch. Unlike the other stories in the series, it wasn't actually written for the planned Season 23, but was a cancelled script from the previous year. It was adapted for audio by Brian Finch's son Peter, and replaced Robert Holmes' "Yellow Fever And How To Cure It" slot in Big Finish's ordering. Peter Finch also wrote a Companion Chronicle starring Liz, "The Sentinels of the New Dawn", which elaborates on the backstory of the secret society.
Tropes:
- Asshole Victim: The Sentinels of the New Dawn all died in stasis after their life support systems were damaged. The Doctor notes that he doesn't like to say that anyone deserves to die, but his experience with the Sentinels prompts the Doctor to observe that basically dying in their sleep is a kinder fate than most of their victims.
- Generation Ship: The Leviathan. The Sentinels placed themselves in suspended animation on a ship they populated with clones, and plan to eventually rule as medieval god-kings.
- Lightspeed Leapfrog: The ship they're on is the titular Leviathan, a massive Generation Ship built just in time for the secret of faster-than-light travel to be cracked.
- Paper-Thin Disguise: At one point the Doctor borrows Father Osbert's cloak and habit as a temporary disguise. He defends the simplicity of it by arguing that he's approximately the same height and build as Osbert, and he's only intending to fool robots who aren't looking for body language cues and other subtler details that humans might spot.
- Secret Test of Character: Peri proves that she isn't part of the Baron's forces when she is clearly ignorant of the purpose of an apparently unarmed crossbow that is actually a laser weapon, even when one of the Pariahs points the weapon at her and threatens to fire it.
- Sequel Episode: This is essentially a sequel to "The Sentinels of the New Dawn", where the Third Doctor and Liz faced the organisation in its relative infancy.
- Tomato in the Mirror: The Baron and some of his associates don't even appear to be fully aware that they are androids before the Doctor confronts them with the reality of the situation.
