Doctor Who's Millie Gibson makes poignant appearance in Christmas special

First though, fans were expecting a one-off adventure for Christmas 2024, with Bridgerton star Nicola Coughlan starring as Joy Almondo in the aptly-named festive episode Joy to the World.

We hadn't expected to see Ruby again until next year... but showrunner Russell T Davies and writer Steven Moffat had planned a bonus Christmas gift for us.

Joy to the World sees a lonely Doctor still getting to grips with losing Ruby, either forgetting she's gone – never have a pair of coffee mugs seemed so poignant – or yearning to speak with her again, shooting longing looks at the telephone of the Sandringham hotel.

His hearts broken, the Time Lord takes to lambasting his enigmatic future self in one powerful scene: "You have to be mysterious all the time... that's why everyone leaves you, that is why you are always alone!"

Eventually, he opens up to hotel employee Anita (Steph de Whalley) about his former companion and how they parted company, finding a little solace in his new friend and their "chair nights" – before getting on with the important business of saving both Joy and the planet Earth from an exploding star.

The episode concludes with Joy embracing and becoming one with the star... and who should we see glimpse the celestial body but Ruby, enjoying life on present-day Earth.

As she stares out of the window, her phone starts to ring... and though we might expect it to be the Doctor on the other end of the call, given he was earlier tempted to reach out, it's actually Ruby's mother calling – following their reunion in last season's finale Empire of Death.

Though we might be denied a Doctor/Ruby reunion – for now – this brief cameo, unannounced prior to broadcast, is a sweet reminder that Ruby Sunday is still out there and will be back in the thick of it with her best friend very soon...

Millie Gibson previously hinted at what viewers can expect from Ruby in season 15, saying: "It's the rare case where you see the companion after the Doctor. It's never been explored before, and I think it's such a beautiful and clever thing to do.

"Can you imagine travelling the world with the Doctor and then seeing how they cope with it after when your life just goes back to normal? It was the weirdest feeling."

She continued: "But yeah, I'm joined by the beautiful Jonah Hauer-King on her journey. He's a very, very interesting character, and he makes the show even more magical. So, I'm very excited to see what he's like."

As for who The Little Mermaid actor Hauer-King will be starring as, we don't yet have any concrete details. However, there are rumours that he's set to star as Ruby's boyfriend – although set photos could point at a bit more of a sinister path for the new character.

Read more:

• Doctor Who - Joy to the World ending explained: What happened in the Christmas special?
• Doctor Who's Russell T Davies and Steven Moffat reveal their favourite Christmas specials

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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