Anthony Read’s interest in adapting the Classics in a sci-fi context threads through stories he script edited, and this, which he wrote. More than that: the idea of the Doctor becoming a mythical figure himself is very attractive (Steven Moffat plays with it all the time). This ends with the jokey implication that the Doctor was around to advise the historical Theseus and ponders on the way that ‘legends are made’ by admirers telling and retelling stories, aggrandising them in the process, so that they last forever. Douglas Adams picks up on this, and reiterates it at the end of Shada. And so, while this is the unintended conclusion of the Graham Williams years, it’s an oddly fitting one, that reinforces the idea that, in the end, ‘it’s all about telling stories. Nothing else matters.’

With that in mind, it feels churlish to dwell on the shabbiness of The Horns of Nimon, except to say that it doesn’t actually look that much worse than much of Season 18, and only looks drab in comparison to the vivid jungle sets of Chloris and Eden, the opulence of the Chateau Scarlioni, or the disco funk of the Movellan spaceship. The terminal decline of Crinoth is suggested by its tumbledown version of the Skonnon labyrinth: corridors stripped bare, panels missing, huge cables snaking about like leeches. Sezon, the Crinothan Soldeed, likewise looks sapped of vitality: hollow-eyed and broken.

Read’s script shows a solid grasp of what’s achievable on the budget: it’s confined to a few rooms, doesn’t require the biggest monster ever, or loads of complicated model sequences. Crinoth’s destruction is represented by a star flaring and fading. You could reasonably argue there’s a lack of ambition, and the conclusion involves a lot of wandering about corridors: this is by no means spectacular. But neither does it include a deadening comedy sequence like the end of Nightmare of Eden. Soldeed’s total mental collapse as his ‘dreams of conquest’ crumble around him is good pay-off, and Graham Crowden’s death scene complete with a deranged giggle, anecdotally a joke performance as he didn’t realise the cameras were rolling, looks properly unhinged. I think this is the weakest story of Season 17, but it’s not a tiresome disaster like Underworld, and the big performances are better integrated even than Lewis Fiander’s Zaroff-lite Tryst.

The biggest disappointment about this is that it’s the end of an era that, season by season, was finding new directions for the show. Season 15 was a nightmare to make, and, occasionally, a chore to watch. Season 16 was a huge step forward, and episode for episode one of the strongest runs in years. Season 17 isn’t exactly better than 16: it’s more uneven and suffers from the Shada-shaped hole that would have wrapped up many of its ideas. But it has an ethos, a life, a spirit all of its own. Williams has balanced the budget across the season so even this, the cheapest one, isn’t recorded on OB in a nursing home. Douglas Adams has polished all the scripts so they have a certain consistency of voice from writers as unalike as Terry Nation and David Fisher. And the fourth Doctor and second Romana actually want to spend time together – not necessarily the case for the last couple of TARDIS crews.

DOCTOR: Other times, other places. Well, come on, old girl. There’s quite few millennia left in you yet.
ROMANA: Thank you, Doctor.
DOCTOR: Not you, the Tardis.

Next episode: The Leisure Hive