The best bits of the serial so far take place inside the Doctor’s brain, where there’s a creditable attempt to create an environment as weird and alien as Axos, supported by strange little gnomic comments like the mind/brain interface ‘the gap between logic and imagination’ where you can’t see one side from the other. There’s also an odd little reference to the Doctor’s ability to tune into the Time Lord intelligentsia having been removed when they kicked him out – an idea of the Doctor as a sort of university drop-out that hovers round the edges of the Williams stories.

On the other hand, the scenes on Bi-Al continue to die harder than a comic on stage at the Glasgow Empire. Leela apparently needs lessons on combat strategy from K9 (as if). The pre-cut wall K9 shoots out looks laughably bad – although I think it’s already meant to have been damaged from the shuttle crash (more damage is visible further down the corridor and there’s rubble on the floor), it’s just poorly set up. There’s a sort of attempt to raise the stakes as the Swarm Zombies close in on the Doctor, take over Professor Marius and almost manage to get K9. This is quite good, but horribly undermined by the final appearance of the Nucleus itself, which replaces the Gell Guards as the worst monster in the show so far. It looks and moves like one of those rubber finger puppet toys from the 1970s.

In many ways this is The Underwater Menace of the Seventies: someone’s read the ‘less horror, more comedy’ brief as an excuse for funny accents, huge eyebrows, daft-looking monster, big performances, and a B-movie plot. Some of the ideas here are operatic, but most of the execution is shabby. Still, not many incoming producers get it right first time. Williams’ approach to comedy will be increasingly sophisticated, even if the show rarely looks as good as it did under Hinchcliffe.

Next episode: The Invisible Enemy – Part Four