Does Doctor Who exist in the Doctor Who universe? Joy to the World moment unpacked

As part of his adventure, he makes use of a bootstrap paradox – where an event causes itself, creating an infinite loop – involving a four digit code he needs to stop the briefcase from disintegrating his new friend Joy (played by guest star Nicola Coughlan).

To do this, though, he needs to while away a year in the Sandringham Hotel, where he makes friends with staff member Anita (Steph de Whalley) in a truly touching bit of TV.

During this sequence, Anita notices the Doctor has collected a number of miniature police boxes which he displays in his room. He says they remind him of home (which we know is the TARDIS) and mentions that he bought them online, briefly puzzling over the fact that there seem to be a lot of them on sale.

So... did the Doctor buy a ton of TARDIS merch from an online Doctor Who shop? And, if that happened, does Doctor Who exist in the Doctor Who universe?

Brilliantly, it's not been the first time this meta joke has been made. In 1988's Remembrance of the Daleks, we hear a continuity announcer introducing "a new adventure in the science-fiction series Doc...". The scene cuts before the full title can be announced.

In the 2014 episode In the Forest of the Night, a poster featuring the Twelfth Doctor, Clara Oswald, and the TARDIS is seen in the background.

So, while it's never been explicitly referenced, there are little jokes and hints that suggest that, somewhere in the Doctor Who universe, the TV show Doctor Who does exist – but, then again, they could all be pure coincidence.

There have been similarly meta moments in the Doctor Who universe rather recently, including the use of Kylie Minogue's song Can't Get You Out of My Head in season 14 episode Rogue, confirming that Minogue exists in the Doctor Who universe.

But Minogue had previously starred in the 2007 Christmas special Voyage of the Damned as new character Astrid.

So, if both of them exist in the Doctor Who universe, did the Doctor politely refrain from mentioning Astrid's uncanny resemblance to Minogue when he met her? Did he not notice?

Either way, you could do worse than puzzling over Doctor Who's meta moments and in-jokes this Chrimbo limbo!

Doctor Who: Joy to the World will air on Wednesday 25th December on BBC One and BBC iPlayer at 5:10pm. Previous seasons are available to stream on BBC iPlayer.

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