When Steven Moffat sat down to write the 2011 Doctor Who Christmas special, he was trying to outdo himself. The previous year he had mined Charles Dickens's A Christmas Carol for inspiration, and in order to make its successor especially festive, he turned his eye to the first book in C.S. Lewis's Narnia chronicles. Although there's no ice queen, no Turkish Delight and no fauns, his final script contains a good deal of the emotional subtext that made The Lion, the Witch and the Wardrobe such a compellingly magical (and surreptitiously festive) tale.

Here are a few things to keep an eye out for, the next time you watch:

(The episode is available on iTunes and Amazon.)

Steven Moffat claimed that this would be the most festive Doctor Who Christmas special ever, although at that point he hadn't written "Last Christmas," with Santa Claus as a character. He told SFX magazine: "If you thought last year’s show was the most Christmassy ever then think again! The Doctor at Christmas—nothing is more fun to write. It’s maybe because it's so his kind of day. Everything's bright and shiny, everybody's having a laugh, and nobody minds if you wear a really stupid hat."

This episode is particularly ripe with British comedy talent. Claire Skinner is best known to British viewers as the mother from Outnumbered, Arabella Weir from The Fast Show, Bill Bailey from Never Mind the Buzzcocks and his stand-up career, and Alexander Armstrong from Armstrong and Miller. Alexander, who plays Reg Arwell is one of a select group of actors to appear in Doctor Who first as a voice and then as a character. He was Mr Smith, Sarah Jane Smith's talking computer, in both The Sarah Jane Adventures and Sarah Jane's Alien Files, reprising the role in "The Stolen Earth" / "Journey's End".

Claire Skinner, who plays Madge Arwell, is married to the director Charles Palmer, already well known to the Doctor Who production team as the man who directed "Smith and Jones," "The Shakespeare Code," "Human Nature" / "The Family of Blood," and more recently "Oxygen" and "The Eaters of Light."

Her father in law is the veteran British TV actor Geoffrey Palmer, who has (to date) appeared in three Doctor Who adventures: Edward Masters in the Third Doctor's first encounter with the Silurians, the Administrator in the Third Doctor story "The Mutants" and Captain Hardaker in the Tenth Doctor's Titanic adventure "Voyage of the Damned."

[caption id="attachment_416525" align="aligncenter" width="976"] Geoffrey Palmer as Captain Hardaker (Photo: BBC)[/caption]

Arabella Weir, who played Billis, has some form with Doctor Who, having played an alternative reality alcoholic incarnation of the Doctor in "Exile," part of the Big Finish audio adventures Doctor Who Unbound, which came out in 2003. This means she was the first woman to play the Doctor in a BBC-licensed Doctor Who drama, Joanna Lumley's spin as a female Doctor in the 1999 Comic Relief spoof "The Curse of Fatal Death" having been too funny to be considered canon. Arabella is also the only American-born actor to play the role, so far.

Arabella is also a very close friend of David Tennant's. He's the godfather to her youngest child, having first met her while working on the Scottish comedy series Takin' Over the Asylum and lodged in her house from 1995 onwards, while he established his career in London.

Lily Arwell was originally named Lucy, in an explicit nod to The Lion, the Witch and the Wardrobe, but it was changed to Lily to keep the script from appearing to be too on the nose.

However, there is nearly a name crossover, in that Madge and her children go to stay at the country house of "Uncle Digby", while in The Lion, the Witch and the Wardrobe, the characters go and stay in the country home of Professor Digory Kirke. In both cases they're fleeing the bombing of London.

There's a slight nod to Back to the Future during the scene where the Doctor presents his model of the house. He says "not quite to scale. Apologies," a sentiment echoed in that of Doctor Emmett Brown about his own model showing Marty McFly how he plans to send him back to 1985: "Please excuse the crudity of this model, I didn't have time to build it to scale or to paint it."

Bill Bailey. who plays Droxil, is such a longtime Whovian, he even created a Jacques Brel-style jazz parody of the Doctor Who theme in 1998, named "Doctor Qui":

https://www.youtube.com/watch?v=68wJIQbCtlI

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