‘Biggest crisis ever and it’s just us. Not the time traveller, not the boy genius, not the supercomputer or the mega-dog. Us.’ At the opposite extreme to Death of the Doctor’s everything-plus-the-sink approach, this strips it all back to just Clyde and Rani wandering a deserted London, facing a baffling alien intervention. It’s a wonderful idea, executed beautifully – you might think with such a small cast it would be the budget one, but all that location filming can’t have come cheap, and the robots, when they finally show up, are tremendous.

As you’d expect, we learn a lot about both characters. Clearly Rani’s academic success and Clyde’s art are known quantities, and their burgeoning relationship gets some clearer focus as Rani declares it’s so good to see Clyde and he picturesquely imagines them as a new Adam and Eve (behave, Clyde). There’s the lovely detail of Clyde’s alienation from his friends and their more mundane lives. What I particularly like is their differences in outlook: Clyde – the artist – notices the details of creepy kid Gavin’s bedroom, which makes him suspicious and mistrustful. Rani is more empathetic, believing Gavin’s miserable life should evoke pity. And these differences threaten to undermine the beautiful friendship that’s been blossoming.

Next Time: The Empty Planet – Part Two