‘The world doesn’t end cos the Doctor dances.’ The elegance of this story is that everything established in the first episode is neatly resolved in the second, in one of the most satisfying pay-offs in the show’s 42-year history. This is phenomenally good, maybe even dishearteningly so: it must have been daunting for Steven Moffat when his first go was near-universally recognised as the best Doctor Who story in at least 16 years, and there’s probably a tiny element of trying to relive this one’s glory (particularly the audacious, hidden-in-plain-sight solution) in every subsequent script for RTD.

What I really like about this is that Nancy isn’t the kind of “impossible girl” Moffat’s sometimes accused of fetishizing. She’s a teenage single mother whose shame at her situation, compounded by the way she’s rejected her child, feels heartbreakingly authentic (helped by the authenticity of Florence Hoath’s performance). The resolution to the story, the Doctor encouraging her to face up to her responsibilities, packs an emotional punch that goes beyond clever plotting, with a humanity that’s not always quite as apparent in some of Moffat’s later high-concept pieces. This is so much a companion piece to Cornell’s Father’s Day that – had it not been a spoiler – could easily have been called Mother’s Day.

And the genius is that this story of a mother reunited with her dead son in the middle of the Blitz is the funniest episode since Douglas Adams stepped away from the typewriter. Moffat brings a decade’s experience of sitcom to the Doctor’s rivalry with Jack, as Rose laughs at them both trying to outdo each other (Jack’s sonic gun trumps the Doctor’s screwdriver, but the Doctor’s screwdriver keeps going like the Duracell bunny, while Jack’s weapon has no stamina – or gets replaced by a banana). The “dancing” metaphor is almost a bit too laboured, but that’s half the joke: it’s not subtle, it’s Rose coming up with a crude innuendo and pushing it as far as she can.

This is as surefooted as the Doctor dancing to In the Mood. Everything lands: horror, humour and pathos. There’s the moment of dread when Jamie’s voice continues after the tape recording runs out (my one criticism is that this moment is repeated, to lesser effect, a few minutes later when the kids hear the clatter of a typewriter and Nancy points out no-one is pressing the keys). Rose telling Nancy, ‘You win’, a recognition that Britain’s finest hour didn’t feel like it at the time. The bathetic pay-off to The Empty Child’s cliffhanger. Jack riding a bomb, and the neat counterpoint of him saving the Doctor and Rose without them noticing, and then having this favour repaid at the end.

Jack’s essentially good-natured character is revealed as he admits he’s a conman but has done his best to make sure no-one is hurt (and Barrowman’s best moment is when Jack is visibly sickened when the Doctor confronts him with the truth of what was inside the Chula ambulance). It even takes time to seed possible future plotlines, with Jack’s motivation (a two-year mid wipe courtesy of the Time Agency). The final scene makes me a bit sad that we didn’t get more of this threesome. The Empty Child and The Doctor Dances is the best debut story since – well, since Rose, I guess. But it’s up there with The Pirate Planet.

Next episode: Boom Town