Doctor Who: Lux ★★★★
Scooby-Doo meets Sapphire & Steel in this animated adventure.

Story 314
Series 15/Series 2 – Episode 2
"We’re going 3D. And remember, whatever you do, don’t make me laugh." – Mr Ring-a-Ding
Storyline
Miami, 1952: at the Palazzo picture house, cartoon character Mr Ring-a-Ding bursts out of the screen and terrorises the audience, who all subsequently vanish. Months later, the Doctor and Belinda investigate the mystery and discover that Mr Ring-a-Ding is the embodiment of Lux, the god of light, and one of the sinister Pantheon. After he converts the time travellers into cartoons, they must use their wits to break back into reality.
First UK broadcast
Saturday 19 April 2025
Cast
The Doctor – Ncuti Gatwa
Belinda Chandra – Varada Sethu
Mr Ring-a-Ding – Alan Cumming
Reginald Pye – Linus Roache
Mrs Flood – Anita Dobson
Tommy Lee – Cassius Hackforth
Husband – Ryan Speakman
Sunshine Sally – Millie O’Connell
Renée Lowenstein – Lucy Thackeray
Logan Cheever – Lewis Cornay
Helen Pye – Jane Hancock
Hassan Chowdry – Samir Arrian
Lizzie Abel – Bronté Barbé
Robyn Gossage – Steph Lacey
Policeman – William Meredith
Newsreader – Ian Shaw
Crew
Writer – Russell T Davies
Director – Amanda Brotchie
Music – Murray Gold
Producer – Chris May
Series producer – Vicky Delow
Executive producers – Russell T Davies, Julie Gardner, Jane Tranter, Joel Collins, Phil Collinson
RT review by Patrick Mulkern
Doctor Who is often at its curious best when it transcends dimensions. Week in, week out, we witness that with the Police Box/Tardis, but when the writer’s imagination stretches even further with, say, the Land of Fiction in The Mind Robber (1968) or the dimension-straddling force in Flatline (2014), the Doctor and the viewers are obliged to think beyond the box.
Lux achieves this superbly. It takes the trappings of cinema projection and celluloid, and capitalises on Disney funds for lustrous animation (actually delivered by British VFX company Framestore), to create an original and increasingly disturbing threat in Mr Ring-a-Ding. He’s like a mix of the Cat in the Hat and an annoying Doctor we haven’t met yet.
The entire middle sequence, where the Time Lord and Belinda are flattened into 2D cartoons but then emote their way back towards their 3D reality, is cleverly realised. The Doctor has long existed in cartoon form on the printed page, but these moments in Lux chime neatly with the variable modern-day attempts to animate the missing 1960s Who episodes.
Fourth-wall breaking is tricky territory but Russell T Davies masters it here – several times over. The cartoon Mr Ring-a-Ding emerges from the cinema screen and becomes "real". The Doctor and Belinda manipulate and speed up the film frames that constrain them, eventually pushing through a TV screen into the living room of their "biggest fans". It’s an audacious stroke and wittily self-reflexive.
When the Doctor asks, "Go on then, what’s your favourite adventure?", his fans say, "Blink, every time." "Not the one with the Goblins?" "Blink!" they insist. Belinda’s disdain for the basic premise of Steven Moffat's classic is hilarious. Even if the outcome of this "bubble" is mawkish, it sets up the quandary: who is real and what is fiction? A theme we’ll no doubt return to this season.
Doctor Who has been getting a lot of stick for raising ISSUES! When handled with subtlety, there should be no objection. So praise for Belinda’s awareness (as a nurse) of the fate that will befall matinee idol Rock Hudson decades later. It should also curl the toes of sentient viewers to realise that, had this adventure not taken place in the dead of night, thanks to racial segregation, the Tardis duo wouldn’t be free agents to visit the diner and cinema in 1950s Miami.
There’s joy in the dark in Lux. "Honey, I’m Velma," the Doctor tells Belinda ("Fred") as they channel Scooby-Doo to check up on an old caretaker in a haunted cinema. But as they explore the mysteries of light, alternate dimensions and missing persons trapped on celluloid, the vibe veers more towards ITV’s old supernatural series, Sapphire and Steel. With more such material, Ncuti Gatwa and Varada Sethu could become an elemental pairing.
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