After last week’s focus on the regulars, the story begins to open up to explain more about the situation they find themselves in. Lobos is the governor of Xeros, ‘a planet in the Morok empire’. The Moroks were apparently once a great spacefaring people, now declining into indolence and decadence. What’s amusing about them is that while the show has attempted to make previous aliens, such as the Sensorites or the Menoptra, ‘otherworldly’, the Moroks are basically bureaucrats with silly hair. They’re the kind of aliens Robert Homes creates. Had Holmes written them they would have been funnier, but probably not by that much. If there’s an issue at all, it’s the performance of Richard Shaw that struggles to land the joke.

The native Xerons are angry young men in black turtlenecks, plotting rebellion against the occupying Moroks (who are all weary and middle aged). In the context of 1965, it’s not that hard to read in some sort of satire. They don’t do a lot in this episode, but they are established as being about as effectual freedom fighters as the Moroks are space conquerors – i.e. not at all. Having captured the Doctor, they immediately lose him. So the comedy is that the TARDIS has landed in the middle of the galaxy’s most incompetent war of independence.

In the middle of this half-arsed struggle, the real danger to the TARDIS crew is the threat of becoming exhibits in the museum. Changing the future is at least explicitly stated as their aim. But they’re about as competent at this as the Xerons and the Moroks are in achieving their goals. The regulars spend their first scene mucking around – it seems half improvised as William Russell waves a space gun about making pew pew noises, and Hartnell meanders his way through the script. There’s some business about a lost button, and then some laboured gags about trying to find the way out when all the corridors look the same. It’s charming because this team is so likeable, but the audience probably sympathises with Barbara as she sighs, ‘We’re just going round and round in circles.’

Towards the end of the episode, the Doctor is captured by the Moroks, and quizzed by Lobos. These are the scenes where Hartnell excels – one on one, a battle of wits. He was great in the courtroom on Marinus, and against Koquillion, and he’s magnificent here. Lit beautifully, face partly in shadow, oozing icy disdain, he mocks and outfoxes Lobos. It’s the high point of an episode which with its rebels vs invaders plot, bureaucratic baddies and endless corridors almost feels seminal.

Next episode: The Search