One of the most distinctive and exciting images from the trailer for Doctor Who’s 2025 season was that of a cartoon character emerging from a cinema screen. It’s the sort of visual that could give younger viewers nightmares, while older viewers can appreciate what the new storytelling possibilities offered by the increased budget. It makes for a pretty spooky opening to Lux, an episode filled with potential that – for whatever reason – it never manages to capitalise on.

After their tense first meeting in The Robot Revolution, it is nice to see the Doctor (Ncuti Gatwa) and Belinda (Varada Sethu) have some fun this week. The Velma gag is a nice touch, while the references to segregation in 1950s America serve as a low-key reminder of the potential dangers of time travel for this specific TARDIS pair. It’ll be interesting to see whether future episodes lean more into this aspect or brush over it the same way as Lux.

A curious creative choice early on comes in the characters’ wardrobe change, shot almost exactly the same way as the Doctor and Ruby’s in The Devil’s Chord in what initially seems like a deliberate choice – how will Belinda respond differently to Ruby? It’s an idea that The Robot Revolution subverts, introducing a reluctant companion on the Doctor’s adventures, but Lux doesn’t continue the subversion, instead diving headfirst into what at times feels like The Devil’s Chord all over again, but with animated films in the place of the Beatles. Ruby being attacked by tentacles of musical notes is mirrored by the Doctor being attacked by film reels, but the latter is much less convincing, and the scene’s dramatic impact is affected by the fact that we’ve seen such a similar scene only last year in a similar episode. Even the projectionist saving the day at the end evokes The Beatles saving the day in The Devil’s Chord, and this is before we delve into the episode’s villain. At Lux’s climax, the initially sceptical Belinda proclaims her newfound trust in the Doctor, but there’s nothing in the episode to truly justify this. It’s as if writer and showrunner Russell T Davies doesn’t want to write a TARDIS duo developing their trust and friendship over the course of the season, which funnily enough was an issue with The Devil’s Chord – which infamously featured a six-month time-jump to find the newly acquainted Doctor and Ruby already the best of friends and skipping over some nice character development in the process.

Mr Ring-a-Ding is a fantastic creation, brilliantly designed and beautifully animated in a way that feels incredibly evocative of ’50s cartoons. Alan Cumming’s vocal performance is pitch-perfect, balancing the silliness of the character with sinister intent. It’s difficult not to be a little bit disappointed with the way the character is used, however. Mr Ring-a-Ding doesn’t really interact with anyone in the episode, presumably because this would have posed a great deal of challenges to the production team, but this ultimately means that we have an exaggerated cartoon character… simply wandering around for the episode. It would have been fun to see Mr Ring-a-Ding devour the audience in the pre-credits sequence or trap the Doctor and Belinda in a cartoonish way. Despite appearing huge at the beginning, a quick line about perspective brushes over why Mr Ring-a-Ding is so short just so that he can grow into a massive Kaiju cartoon at the end. The ‘twist reveal’ of course is that he’s actually Lux, one of the Pantheon of Gods (encompassing the Toymaker, Maestro and Sutekh, which the episode takes great pains to spell out to the audience), who has… possessed this animated character? The script – at least on a first viewing – is pretty unclear about this. Are the Doctor and Belinda facing off against Mr Ring-a-Ding or Lux presenting as Mr Ring-a-Ding? Why does he have to join in with the song when it plays on screen? If his powers are light-based, how can he physically move projectors with his mind? Even when the Doctor and Belinda become animated, it’s for a very brief moment that perhaps shouldn’t have been revealed in the trailers. There’s even a running theme about three-dimensional characterisation resulting in literally three-dimensional animated characters, which almost comes across as dismissive towards two-dimensional and hand-drawn animation. It’s hard to believe that that’s Russell T Davies’ authorial intention, but it’s an odd plot point, nevertheless.

Speaking of odd plot points, this week Doctor Who broke the fourth wall completely by having the Doctor and Belinda emerge from a television to meet…Doctor Who fans. What initially seems like a cheap gag – along the lines of Red Dwarf’s Back to Earth – quickly becomes an overly-sentimental sequence that’s probably intended to be a meta-tribute to the programmes’ dedicated audience but feels misplaced. As Murray Gold’s reused score from the Series 5 (2010) soundtrack blasts at full volume, it’s difficult not to wonder if this is a meta gag in and of itself or simply recycling existing music (which happens earlier in the episode anyway). Gold is a talented composer, but it’s difficult not to wonder if a new composer could have brought a new musical identity to this era of the show.

All in all, Lux is a great idea for a Doctor Who episode that never manages to become a great a Doctor Who episode. The ambition is admirable, and the opening act has a great sense of atmosphere, but it feels restrained all the way through. Mr Ring-a-Ding doesn’t really do anything as the main villain, the meta-gags with the Doctor and Belinda trapped in the film either feel too short or too meta for their own good, and just in case the episode didn’t feel familiar enough we get a cameo from Mrs Flood (Anita Dobson) pointing out the TARDIS dematerialising. On Doctor Who Unleashed, Russell T Davies refers to this instalment as “one of our Mad God stories”, a formula which is already feeling a bit stale (despite the storytelling possibilities implicit within such a premise). Lux is by no means a bad episode, but it is a disappointing one. Here’s hoping that the eerie-looking The Well sends us back behind the sofa next week.

Doctor Who returns to BBC One next Saturday at 19:20

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