Terry Nation has decided to give this story a theme, with all the subtlety he displays when naming planets. So we have several moments where the Doctor reflects on the difference between recklessness and courage, condemning Vaber’s hot-headedness and praising Codal’s self-sacrifice. It all boils down to “feel the fear and do it anyway”. Thanks for attending this Ted Talk.

Self-sacrifice is something the Doctor has in abundance. The Daleks have tracked down the crashed Thal spaceship – where the Doctor believes Jo to be hiding out. When a squad of Daleks surrounds it and prepares to destroy it, the Doctor leaps out in front of them and warns them someone is still inside, which feels like practically the most stupid thing you could tell a Dalek in this situation. Still, it’s nice that for once it’s the Doctor leaping in front of a bullet meant for Jo rather than the other way round, and very lucky indeed that the Daleks demonstrate their stun gun setting for the first time since their original story.

Terry Nation’s old school approach to the series is fairly evident: this is all very straightforward Dan Dare stuff, reliant on Pertwee and Horsfall’s performances to carry it. The Doctor’s evident anguish at Jo’s apparent death, and his devastated look when he listens to her recovered audio log give the episode a bit of emotional heft. Meanwhile, Horsfall’s weary but unbowed face-off against Prentis Hancock’s shouty Vaber gives some fairly nondescript macho dialogue a bit of oomph, and his reaction to the cliffhanger reveal that there are 10,000 Daleks secreted on the planet is pretty stirring.

Next episode: Planet of the Daleks – Episode Three