Carnival of Monsters succeeds where The Time Monster failed, by actually having story that progresses week on week, alongside larger-than-life but credible characters. On paper, the plot of the episode seems thin: the Doctor and Jo escape from the SS Bernice into the circuits of the miniscope, emerging in a swamp where they’re menaced by Drashigs. Meanwhile, Vorg and Shirna must convince the paranoid Inter Minorans that they are not Lurman spies smuggling in dangerous alien monsters to bring about the downfall of the government. It’s hardly Gravity’s Rainbow, but each scene feels like it’s advancing the story, and there’s no obvious fat (rather scenes cut to the chase – for example when Vorg turns the aggrometer up we switch straight back to the Doctor squaring up to Andrews).

I really like how deftly each of the characters is brought to life. In The Space Pirates Milo Clancy was a recognisable type with a familiar idiom. Holmes has honed this approach so now all the characters are similarly vivid, and Letts has cast the roles in perfect keeping with the script. So Tenniel Evans is the bluff old colonel, the Inter Minorans are all prissy bureaucrats, gossiping and pedantically sniping at one another and so on. And because we instantly get the characters, the weird, colourful outer space setting is strangely easier to accept than cod-Shakespearean types declaiming earnestly about revolution, or panto butterflies wafting about.

Which means the utter strangeness of the Doctor and Jo being shrunk to about an inch tall and wandering about the innards of an electronic space zoo almost goes without comment. The mystery isn’t what is happening – last week’s cliffhanger pretty clearly established the relationship between events on Inter Minor and the SS Bernice – but how the Doctor and Jo’s adventures in the miniscope are having an unwitting impact in the wider world. Their surprise appearance (and failure to behave like human goldfish) perplexes Vorg and Shirna and positively chills the Inter Minorans. It’s lovely to see Pertwee and Manning spending so much time doing old-school Doctor and companion adventuring in outer space. Given this is the anniversary series it’s also nice to see the return of the Cybermen and the Ogrons (the latter also serving as a nice refresher ahead of their return in the next serial). And the Drashigs look great. This is brilliant.

Next episode: Carnival of Monsters – Episode Three