One of Doctor Who’s great folk tales regards Sydney Newman’s reaction to Terry Nation’s first story for the series. How he complained to producer Verity Lambert that this tale of – what were they called again? Dar-leks? – was exactly the sort of sci-fi pulp he wanted the show to avoid. Lambert famously denied this was a b-grade bug-eyed monster fest by pointing out the story’s deeper themes of fear and warfare and how it warned against a future where we ourselves had mutated into hate-filled isolationists.

Upon the great success of that story, Newman admitted that Lambert had been right and it was time for him to keep his nose out of a show which had become an overnight hit. Still, I wonder what he must have made of The Keys of Marinus, Nation’s second story for the show. Because try as I might, I can find no deeper message in this story of an amazing race around the adventurous locales of Marinus, each one hurriedly assembled in Lime Grove Studio D. It’s truly midday matinee adventure stuff, with none of the subtext which Lambert had used to champion The Daleks. Its rubbery villains, the Voords, have handlebar horns rather than bug eyes, but that’s probably only because a cash strapped production ran out of poster paste with which to affix them.

I exaggerate. I suppose in the idea of the Conscience of Marinus, an all-powerful justice machine which governed and then oppressed its creators, there is something of the familiar 1960s trope of “the machines are getting too big for their transistorised boots” (for more of which see The War Machines, The Ice Warriors and The Invasion, to name but three). By the time we’ve traversed over jungle, tundra and the city of judges with absurd hats, the Doctor (William Hartnell) is ready to spell out the story’s flimsy moral. “Machines can make laws, but they cannot preserve justice,” he opines to young Marini-lass Sabetha (Katharine Schofield). “Only people can do that.” There’s none of The Daleks lightness of touch when it comes to the message of the story. Only a Pertwee-esque moment of charmless lecturing.

Ironically, if Newman was looking for any of the subtlety and imagination he thought should be the series’ trademark, it’s to be found in the episode with the bug eyed monster brains. It’s the trippy The Velvet Web and in it, our travellers are hypnotised into believing they are in a utopian palace where they can be supplied with whatever they desire. Only after the spell wears off on Barbara (Jacqueline Hill) do they discover that the comforts and riches surrounding them are illusions, and are part of a trap to enslave them by a group of brains with eyes on stalks. Exactly why the talking brains want a group of gormless human lackeys is never made clear; to polish their cases, I assume, and occasionally move them closer to the telly or something. Or maybe it’s just to make them walk around in their speedos, ala young drip Altos (Robin Phillips). No wonder those eyes are popping out of their frontal lobes.

Still, at least here are the themes of the destructiveness of self-delusion and dangers of a geniocracy, without the Doctor having to spell it out in the final reel. No, he’s got better things to do. He’s read the scripts for the next two episodes and decided to skip closer to the story’s end. Unfortunately, the audience is left wishing he’d taken them with him.

It’s sometimes pointed out that in the earliest days of the show, the series was an ensemble affair, but in reality, Hartnell quickly established himself as the main attraction. Not that Barbara, Susan (Carole Ann Ford) and Ian (William Russell) aren’t engaging company, but they’re no Doctor and the episodes without him are diminished. The third, The Screaming Jungle is a forgettable affair of lush, aggressive vegetation and the fourth, The Snows of Terror, would be just as unremarkable, except that it includes a misjudged moment where huntsman Vasor (Francis de Wolff) attempts to force himself upon Barbara.  I mean, when an attempted rape is the most notable thing about an episode of Doctor Who, we really are on fallow ground.

The Doctor returns for the last two episodes in which Ian is framed for murder in a city where there’s a presumption of guilt, rather than innocence. Murder mysteries require some murderers, of course, and at this point, viewers may have been wondering if the internal logic of the story was a bit wonky. In the first episode, a wise old man called Arbitan (George Colouris) had wandered around explaining the plot, while looking as forlorn as only a man who once starred in Citizen Kane and has now found himself in The Keys of Marinus can. Arbitan had said that the Conscience had eliminated wrongdoing from this planet by influencing the population’s behaviour. How then to explain, how everywhere our intrepid key seekers go, they find people up to good? Murderers, liars, rapists and disembodied evil brains. Presumably the aura of niceness was upset when Yartek (Stephen Dartnell) meddled with it, but that’s quite a lot of wickedness which sprang up in a (presumably) short amount of time, after centuries of good behaviour.

The murder mystery of Millennius struggles to capture any interest, partly because much of the acting is hammy and involves complicated relationships between characters who all look and sound the same. Only crafty Kala, played with relish by Fiona Walker, stands out, and then mostly because apart from spaced-out Sabetha, she seems to be the only other talking woman on Marinus. In any case, the city of Millennius seems like a difficult place to commit a crime. Its inhabitants are prone to blurting out their nefarious plans in “I got so excited I forgot to not say anything to indicate my guilt!” moments. Even Hartnell can’t quite bring himself to try and liven up events. Great though it is to have him back, I bet he was thinking enviously about whether he could have gotten away with another week’s holiday.

If he had, he could have just rejoined the story for its last, unlikely episode where everyone is fooled by Yartek pretending to be Arbitan. In a masterstroke of disguise, Yartek simply pulls his hood over his head. Never mind that his rubbery handlehorns make his head look about twice the size of Arbitan’s. Never mind that he doesn’t sound anything like Arbitan. And never mind that this villain who brought an entire planet to its knees is fooled by a simple substitution of one genuine key for a dodgy bootleg one. Perhaps all that rubber has constricted his brain.

Look, it’s clear The Keys of Marinus is not my cup of tea and that’s because it’s simplistic, cliched hokum which asks little of its audience. I’d like to think everyone in the production office at that time – not just Sydney Newman – recognised it as exactly the sort of b-grade sci-fi fare they’d been trying to avoid making.

But then again, maybe not. Maybe from another perspective, that’s mostly what Doctor Who is and Nation was actually pioneering a form of undemanding, tea time adventure for kids which would become the show’s default setting. Maybe, and perhaps slightly depressingly, Nation was proving that there’s nothing wrong with bug-eyed monsters and that Doctor Who could work without pretentions to educating kids or embedding layers of subtext. Take that Newman! Pop pop pop.

LINK TO Warriors’ Gate: both feature sumptuous feasts, which are subsequently revealed to illusions.

NEXT TIME: Medicine, science, engineering, candyfloss, lego, philosophy, music, problems, people, hope. Mostly hope that we’ll solve The Tsuranga Conundrum.