Brilliantly, the resolution to last week’s “monster reveal” cliffhanger is the Doctor extending his hand and asking, ‘Hello, are you a Silurian?’ This feels like the first indication that some thought has been put into making the new Doctor a different flavour than the old one: reaching out the hand of friendship to alien life forms rather than darkly contemplating corners of the universe that have bred the most terrible things.

I think this is also where the third Doctor comes into his own. Pertwee was a less versatile actor than Troughton, although I think this can be overstated, but he brings a superior ability to treat men in rubber suits as the most natural thing in the world. There’s an old convention anecdote he used to tell to illustrate how he once had a conversation with an actor dressed as a Draconian and “forgot” he was talking to a man in a costume, but treated him as if he really were from outer space. And you can absolutely see that in Pertwee’s approach to this script: his response to the Silurian, reaching out to shake its hand, on one level is as funny as Troughton pulling a face and cowering in terror. But his ability to treat monsters as people sells them as effectively as Troughton playing scared.

It also helps that the Silurians are shot quite sympathetically, mainly appearing in murky, dimly-lit settings like the gloomy front room of Dr Quin’s cottage or the caves (and the slightly muddy colour restoration helps as well). Plus there are enough nice details in the Creature from the Black Lagoon style costumes – the alligator spine, the clawed hands, and the lizard masks – to distract from their overall rubberiness. They look better than the Ice Warriors in colour. It’s also really fun how their third eye mirrors the head torches on the caving helmets.

The rest of the episode riffs off the opening scene, with the Doctor’s desire to find a peaceful accord between human beings and Silurians frustrated by Major Baker’s hero complex, the Brigadier’s military mindset, and Dr Lawrence’s prissiness (there’s a lovely scene where Peter Miles visibly seethes at his cocky subordinate Travis). The arrival of the civil servant Masters gives a chance for everyone to get caught up on the plot- for those who have joined late or have lost the thread a bit across the last month, and need a reminder going into the second half of the story.

It’s not hard to see how this is likely to play out, with both the humans and the Silurians preparing for conflict. The mystery remains whether the Doctor will be successful in negotiating a truce. His return to the Silurian base to open negotiations that neither side wants leads into a brilliant reveal: ‘This planet is ours: it always has been.’ This isn’t an alien invasion, it’s a civil war.

Next episode: Doctor Who and the Silurians – Episode 5