"The Lodger" is a companion-lite story, one in which the Doctor abandons his best friend of the moment and meets new people for a new adventure. But the twist is that his brave new world is the domestic reality of modern single life, an utterly alien concept for him, but all too familiar for a great many Doctor Who fans.

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

(The episode is available on iTunes and Amazon.)

Gareth Roberts originally wrote the story "The Lodger" as a comic strip for Doctor Who Magazine. The essential story arc is the same, in that a TARDIS malfunction leaves the Doctor stranded on contemporary Earth, with an alien upstairs. Only it's the Tenth Doctor, and he bunks with Mickey Smith while he waits for Rose and the TARDIS to arrive a few days later. When he came to write the TV version, Gareth started the idea from scratch, to fully explore what it would be like for the Doctor to experience domestic life on Earth.

The original plan was to make Neil Gaiman's "The Doctor's Wife" part of Season 5, but it was clearly going to be quite a costly story to film properly, and technically quite demanding, so "The Lodger" was conceived as a story that would be relatively cheap to make. "The Doctor's Wife" appears in Season 6.

The Doctor makes Craig an omelet, which may well be a subtle nod to co-star James Corden's hit TV comedy Gavin and Stacey. Co-written by James and Ruth Jones, the show's action plays out almost entirely in domestic locations, and Gwen, Stacey's mum, seems to cook an endless supply of omelets whenever anyone appears to feel hungry.

If you look at Craig's fridge, there's a postcard flier for the Vincent van Gogh exhibition at the Musée d'Orsay in Paris, the very one that the Doctor took Vincent van Gogh to in the previous episode, "Vincent and the Doctor." Similarly, there's a van Gogh sketch depicting a wheat harvest on the Doctor's bedroom wall.

[caption id="attachment_405333" align="aligncenter" width="1004"] (Photo: BBC)[/caption]

When the Doctor imparts the full knowledge of his previous incarnations to Craig using telepathic headbutts, he says, "Eleventh" amid all the gasping. This is the first time the Doctor has put a number to his various incarnations within the new series. It's interesting to note that even while telepathically dumping his life history into another being's head, he refuses to disclose anything about the War Doctor.

https://www.youtube.com/watch?v=3_FcNoOPC-E

Matt Smith absolutely has the soccer skills to carry off the scene in which the Doctor wins the football match for Craig's team — a legacy of years of training in the youth teams for Northampton Town, Nottingham Forest and Leicester City that would have seen him become a professional footballer had he not had to retire after a back injury. But that scene was not conceived with him in mind. The concept was carried over from Gareth Roberts' original comic, and in fact Gareth wrote the first draft of the script with no idea of who the Eleventh Doctor might be.

The Doctor's soccer jersey has the number 11 on it, which is a reference to him being the Eleventh Doctor, but "The Lodger" is also the eleventh episode of Season 5.

In the scene where the Doctor takes a shower, he can be heard singing "La donna è mobile," the Duke of Mantua's canzone from act 3 of Giuseppe Verdi's 1851 opera Rigoletto. It's an aria that he has sung before. The Third Doctor sang it to himself while driving his car Bessie, in the alternate reality epic "Inferno."

https://www.youtube.com/watch?v=xCFEk6Y8TmM

When the Doctor hands Craig his rent money in cash, he says "Don't spend it all on sweets, unless you like sweets. I like sweets." The Ninth Doctor said exactly the same thing (apart from the extra stuff about liking sweets) to Adam Mitchell when he took him into the future and handed him a credit stick in "The Long Game."

The Doctor introduces himself to the time ship as "Captain Troy Handsome of International Rescue," which is an affectionate homage to the work of puppeteers Gerry and Sylvia Anderson. Captain Troy Tempest was a character in their underwater epic Stingray, while International Rescue was the family-run emergency organization in Thunderbirds:

https://www.youtube.com/watch?v=E06cNv55jTs

NEXT: 10 Things You May Not Know About ‘The Pandorica Opens’

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