Leela’s execution by steaming as presented in Terrance Dicks’ novelisation always filled me with horror as a child and went a long way to making this one of my favourite Doctor Who books. For all this is largely a comedy, Robert Holmes doesn’t skimp on the scares, and when it comes down to it, Tom Baker doesn’t undercut them by playing for laughs. The moment when he realises Leela is to be killed in a particularly gruesome way, there are no one-liners or mucking about: he looks stressed out, if anything, snapping at K9 to get on with it, and forgetting any other distraction as he single-mindedly focuses on a rescue plan. None of this feels remotely silly.

Had this looked more like Season 14’s SF gothic, rather than the proto-Blake’s 7 we get, I think it would be easier to see this as a piece with The Deadly Assassin. Instead, some of the colourful sets and costumes, Richard Leech and Henry Woolf’s comic performances, and K9 tend to make this feel more different than the script really is. But the Collector isn’t a comedy villain: as soon as he actually puts his mind to it, he’s worked out who the Doctor is and, more importantly, understood that there will be no bargaining with him: ‘He has a long history of violence and of economic subversion. He will not be sympathetic to my Company’s business methods.’ Quickly executing Leela to try to bring the Doctor into the open, rather than keeping her hanging round in a cell to be rescued, does almost derail the tentative rebellion.

And there are other surprisingly brutal bits: the Doctor’s torture at the hands of Mandrel’s men includes a fairly vicious-looking punch in the stomach. The Doctor’s facetiousness fades against the grim reality of a bunch of grizzled criminals, and becomes defiant rather than flippant. This then leads to a fairly unusual scene of the fourth Doctor having to incite a rebellion, and the oddly perturbing sight of David Rowlands towering even over Tom Baker. Leela is put in a straitjacket and interrogated, and again it’s disturbing to see her so powerless.

Plus, Holmes’ grasp on the characters remains first class. A trained hunter, Leela lures the pursuing Inner Retinue squad into a trap, but comes a cropper because of her (Fang Rock style) gloating. After even Chris Boucher failed to make much use of her in Image of the Fendahl, and she had to be instructed in tactics in The Invisible Enemy, this feels much more like the Leela of old. K9 gets something only he can do: trundling into a pressurised shaft that the Doctor can’t crawl through. This is a blisteringly good third episode.

Next episode: The Sun Makers – Part Four