The risk of a story like this is that, like a Terry Nation script, it can be prolonged almost indefinitely by bunging in another confrontation with a creature from literature or legend. So it’s to the story’s credit that not only do the episodes run shorter than usual – this clocks in at 19 minutes – but that there’s some thematic coherence and structure that prevents this from feeling like a piece of derivative whimsy.

Here, the design and script combine to make it a journey into the heart of the spider’s web. That’s both literal, given the team have to battle through a forest of cobwebs to get into a creepy haunted house, and figurative – with Jamie finding his way into the sci-fi heart of this fantastic realm, while the Doctor and Zoe make their own journey to the heart of the minotaur’s maze (which even looks like a spider web design). And squatting in the centre of it all, like an obscene attercop, is the lurking Master, growling his orders to his clockwork soldiers.

It’s also quite funny, particularly Zoe’s appalled reaction when the Doctor sheepishly admits it was him that got Jamie’s face wrong the first time he had to put it together – and Wendy Padbury’s smiles of encouragement as he re-takes the test are as sweet as anything. And while Zoe and the Doctor finally get chance to spend some time as a team, Jamie manages to woo Rapunzel before discovering the ‘work in progress’ ticker tape machine that, brilliantly, seems to be writing the script of the episode as it’s acted out. It’s a beautifully modish moment of playful 1960s’ surrealism that’s Beatles-esque in its offhand cleverness.  

While it’s light on plot, and the sets make a lot of use of black space, this only adds to the experimental, theatrical feel of the piece. The Doctor chatting with Gulliver while Jamie chats up Rapunzel, and the reveal that it’s all a Land of Fiction is all carried off with a lightness of touch that lifts this well above the show’s previous, much more prosaic venture into childlike weirdness, The Celestial Toymaker. This is great.

Next episode: The Mind Robber – Episode 4