Looking past some of the design deficiencies (the green plastic furniture on Gallifrey is horrid, and makes this look like Bi-Al’s Kasterborous branch) this is pretty good. I really like the location filming, which – intentionally or otherwise – has the burned orange sky Susan mentions in The Sensorites, and has become the template of Gallifrey for the new series in a way that the blasted heath of The Five Doctors hasn’t.

The idea of a society of Time Lord drop-outs going back to nature, rather like all those burned-out stockbrokers and managers in the 1970s, and then coming face to face with a real child of nature is fun. Leela’s finally in her element, having felt like a fish out of water in the confines of the Capitol. Louise Jameson is brilliant as ever, and gets the best lines in the episode – ‘Now we can fight them,’ when the Vardans reveal themselves, and ‘Then reason is a liar’ when confronted with Rodan’s logic.

Inside the city, I really enjoyed Tom Baker and John Arnatt’s scenes: the Doctor and Borusa hardly interacted in The Deadly Assassin; this gives much more a sense of the old teacher/student relationship, and a genuine sense of grudging affection. Arnatt is to Borusa what Andre Morell is to Quatermass. The Doctor’s ability to resist Vardan telepathy because of his scattergun thinking, and Borusa’s half-amused realisation that his own disciplined mind wouldn’t last five minutes, is great. In general, Tom seems to really be enjoying himself in this: flashing the Sash of Rassilon like he’s a dirty old man, and playing up his megalomania for the benefit of the toadying Castellan.

One thing that annoyed me though: in the last episode Gomer is said to be ‘young’ but here he’s said to be very old, and on his 10th regeneration. I suspect he’s the real Timeless Child.

Next episode: The Invasion of Time – Part Four