Doctor Who's Anita story is completely unexpected – and utterly heartbreaking

There's a lot going on – and that's before we get onto a Silurian cast adrift in history, an encounter with a dinosaur, the Doctor's role in the very first Christmas and his brief but transformative meeting with the aptly-named Joy Almondo (played by Bridgerton lead Nicola Coughlan).

But, surprisingly, the richest vein that Moffat mines in this story, the episode's most poignant plot strand, has nothing to do with any of that.

The heart of Joy to the World lies in Anita Benn, a seemingly unremarkable hotel employee played by Steph de Whalley. (But don't forget that Eleventh Doctor quote from, fittingly, another of Moffat's festive episodes: "I've never met anybody who wasn't important.")

Early on in the episode, in a trademark bit of time trickery, Moffat has the Doctor exploit the special qualities of the Time Hotel to get away with a bootstrap paradox – where an event causes itself, creating an infinite loop.

Here, a future version of the Doctor arrives to provide his past self with a four-digit code that he needs to save Joy's life, a piece of information that future-Doctor only has because he'd previously heard it from his own future self...

In order to reach the point at which he becomes future-Doctor and can travel back to rescue Joy, present-Doctor has to while away an entire year at the Sandringham hotel.

This narrative element could have unfolded as a brief montage and been played entirely for laughs, something akin to the sequence in 2012 episode The Power of Three in which the Doctor (Matt Smith) busies himself with household tasks to try and pass the time...

Where the episode goes instead is somewhere entirely unexpected – and wonderful.

We begin, predictably enough, with the Doctor taking up a job at the hotel to stave off boredom, unable to resist using a whizzy gadget or two to lighten his workload – but while he's looking for nothing more than a distraction, what he ends up finding is a friend.

We first meet Anita when Joy checks into the Sandringham – she makes a few fleeting appearances in the episode's first act, most notably serving as light relief during an awkward encounter between the Doctor, Joy and Melnak the mind-controlled Silurian (Jonathan Aris).

Steph de Whalley nails the comic beats required of her, and one might assume that's the last we'll see of her – but in fact Anita becomes the star of her own quite beautiful sub-plot.

As the days, weeks and months pass, the Doctor and Anita grow closer, both having recently parted ways with someone they loved. She helps him rediscover his love for the little touches, those quirks and foibles that make us human, and reminds him that a cold, clinical TARDIS or a bare-bones hotel room may be somewhere to spend your time, but it is not a home.

For that, you need friends, you need family... you need chairs.

With his new companion – yes, we're going there – at his side, our nomadic hero, his days like crazy paving, gets to experience a life lived day-by-day and the wonders it brings. (Yes, if you're being pernickety, he also experienced this not long ago as the Fourteenth Doctor, kicking back in a cute country home with the family Noble, but let's be generous and assume those events took place a fair while ago from the Fifteenth Doctor’s perspective.)

It's his experiences with Anita, as much as his subsequent adventure with Joy, that remind the Doctor he needs a friend, that he needs to be seen through someone else's eyes to remind him when he’s losing touch.

De Whalley acquits herself admirably throughout, showing herself capable of so much more than her first scenes demonstrated as Anita in turn has her eyes opened by the Doctor to the joys of the world – no pun intended – and finally as she experiences the inevitable heartbreak, as all his companions eventually do, of saying goodbye.

Nicola Coughlan might be the episode's big-name signing, but in her scenes De Whalley proves herself an equally worthy co-star opposite Ncuti Gatwa in a sub-plot so touching and delightful that you share her feelings of disappointment when the time arrives for the Doctor to leave so the A-story can resume.

So on the Time Lord goes... but Anita is one auld acquaintance that should never be forgot.

Read more:

• Doctor Who - Joy to the World ending explained: What happened in the Christmas special?
• Doctor Who's Millie Gibson makes poignant appearance in Christmas special

Doctor Who will return to BBC One and BBC iPlayer in 2025. Previous seasons are available to stream on BBC iPlayer.

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