"The Doctor Dances" has one of the most satisfying conclusions to a Doctor Who story, in that a damning foregone conclusion is overturned by the very alien invaders who started all the problems in the first place. We also get to see the joy and relief on the Doctor's face, as for once he finds himself involved in an adventure with a happy ending for all concerned.

Here are a few things that you should keep an eye out for, the next time you watch. (The episode is available on iTunes and Amazon.)

Steven Moffat is rightly proud of the line "Life is just nature's way of keeping meat fresh," so much so that this is actually the second time he has used it. It first appeared in his BBC sitcom Joking Apart (1993-95).

Having scouted out the Cardiff Royal Infirmary for the location of the hospital wing used in this episode and the hospital used in "Aliens of London," it was decided to create a moment of temporal synchronicity and say it's the same place—named the Albion Hospital—at different points in time.

Steven Moffat told Doctor Who Confidential that he believes that the Doctor kept hold of Captain Jack's sonic blaster (as used to take square holes out of the walls and floor, and then fill them up again) and put it in the TARDIS for future use. River Song will come across it at some point during her travels with the Doctor and use it to help them in "Forest of the Dead."

It's also interesting to note that the Doctor has form when it comes to replacing guns with bananas. He does it here and in "Let's Kill Hitler," and of course it's implied that he blows up the Weapon Factories of Villengard, replacing them with a banana grove, because "bananas are good."

Which does at least explain how he got hold of one in wartime London.

https://www.youtube.com/watch?v=4EpreukySEQ

Mr. Lloyd, who receives such a blistering telling-off from Nancy, is played by Damian Samuels. Sherlock fans may remember spotting Damian trying to escape being shot at by "The Abominable Bride" in the recent Victorian Christmas special:

[caption id="attachment_360423" align="alignnone" width="1122"] Damian Samuels as Giles in 'Sherlock' (Photo: BBC)[/caption]

Meanwhile, Luke Perry, who played Mr. Lloyd's son Timothy (who gives Nancy a fright when he turns up at the house in a gasmask, looking like The Child), later went on to appear in Torchwood: Children of Earth as David Davies.

All the way through Season 1 there are Bad Wolf clues, but none quite as explosive as in this episode. The bomb Jack ends up riding down to the Doctor and Rose (which is itself a nod to Stanley Kubrick's Dr. Strangelove), has Schlecter Wolf stenciled on it. This is the subject of a report on the website Who is Doctor Who?, complete with a link to a UNIT briefing about the bomb, which concludes: "We've been hearing reports of people creeping onto construction sites to see if they can steal something. Apparently, these shells are interesting in design, and, what with eBay, the market for World War II artefacts has really exploded. We'd urge people to keep away—these shells aren't so much special as lethal."

Steven Moffat is particularly fond of putting verbs in his script titles, and that's a rarity for Doctor Who. Even in the early 1960s, when every new episode had its own title, it wasn't until the second series that a verb appeared, in the episode of "The Romans" called "All Roads Lead to Rome." This was followed a whole series later with the "Don't Shoot the Pianist," part of "The Gunfighters." After that it's a verb desert, even the Fifth Doctor story "Four to Doomsday" avoids putting a verb in (when one might actually be rather useful).

By contrast, in the rebooted Doctor Who, there have been 12 episodes with verbs in the title—"The Doctor Dances," "Fear Her," "Blink," "Turn Left," "The Pandorica Opens," "A Good Man Goes to War," "Let's Kill Hitler," "The Angels Take Manhattan," "Listen," "Kill the Moon," "Sleep No More" and "Face the Raven"—of which five were written by Steven Moffat.

https://www.youtube.com/watch?v=jhklrve5xmw

"Don't forget the welfare state," yells the Doctor to everyone he has just saved. That's because, as soon as the war is over, a general election will be held that elects a strong Labour government, ready to meet the vision of Liberal politician William Beveridge. He had been set the task of finding out what kind of country the Brits would like to live in after the war, and found five obstacles to happy nation—poverty, disease, ignorance, squalor and idleness. He proposed a welfare state, with social security, a national health service, free education, council housing and full employment. And in 1945, a Labour government was elected that sought to realize that vision, to pull the country back together after years of turmoil.

Towards the end of the production, it was discovered that "The Doctor Dances" was a little short in its running time, so Steven Moffat came up with the scene in which Nancy tells the orphans that she's the one the child is chasing, as is confirmed when the typewriter becomes possessed.

Doctor Who Confidential confirmed that most of the conversation around "dancing" in this episode is using it as a code for what we shall blushingly call "romance." Which casts a new light over all the lines about whether the Doctor can dance, with Rose assuming that he's past it, and the Doctor complaining that he used to know how to to it. It's a theme Steven Moffat returned to in his very next Doctor Who script, "The Girl in the Fireplace."

And should you ever wish to find a decent Whovian line for those moments when romance is not on the cards, it's tough to beat "Rose, I'm trying to resonate concrete."

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