
The thing about writing these spoiler-free Doctor Who reviews is that sometimes you hit an episode that is defined by a scene in the episode that, for obvious reasons, we can't talk about just yet. That's the case with 'Lux,' the bold, bonkers second episode of Ncuti Gatwa's sophomore season – a story that doesn't so much swing for the fences as bulldoze right through them.
'Lux' picks up moments after 'The Robot Revolution' with the Doctor still trying – and failing – to get Belinda home. He at least manages to reach Earth, but in the wrong decade and location. Rather than London in the 2020s, this is Miami in the '50s. Still, there's a shut down cinema and 15 missing patrons to investigate.
A two-dimensional villain – literally

If that all sounds a bit Scooby-Doo, well, writer Russell T Davies beat you to it with a laugh out loud gag. The Doctor and a semi-reluctant/semi-intrigued Belinda break into the cinema and immediately encounter something entirely unexpected: a living cartoon.
This is Mr Ring-A-Ding, a malevolent 'toon straight out of the rubbery Max and Dave Fleischer school of animation (think Popeye or Betty Boop). He's not confined to the cinema screen either. In a moment that plays not unlike a family friendly twist on Japanese horror classic Ringu, Ring-A-Ding is able to crawl right out of the screen.
Doctor Who, even in the Disney Plus era, has not always been blessed with the most convincing special effects, of course, but Ring-A-Ding is a wonderfully realized creation, both in terms of execution and sheer strangeness. Belinda, speaking for the audience, is amusingly baffled by what he – with his blue skin and pig nose – is actually even supposed to be.

The Doctor, of course, is delighted by all of this right until he realizes the magnitude of the threat this literally two-dimensional villain really poses. Ring-A-Ding may have certain limitations (he is a cartoon after all) but what he also has in spades is creepiness. He's voiced with sinister glee by Alan Cumming, marking the sometime X-Man's second appearance in the Whoniverse following an entertaining turn as King James I in the Jodie Whittaker-era story 'The Witchfinders.'
Something new

Ncuti Gatwa, it has to be said, is absolutely terrific in this episode. I noted in my review of 'The Robot Revolution' a certain chilliness to his Doctor this time around. I was thinking of the moment where he calmly compartmentalizes Sasha 55's sudden death – a scene that reminds you that for all his loveable quirks, the Doctor is something other than human.
In 'Lux' Gatwa embodies every facet of the character, from his usual puppyish joy to a more pronounced universe-weary melancholy that recalls Sylvester McCoy's mysterious, mercurial Seventh Doctor. He's quietly tender one moment when consoling a grieving mother, calmly furious the next while staring down the prejudices of the era. It's Gatwa's best performance in the role to date, and I'm fascinated to see how his character will develop in the coming weeks.

Belinda's quest to get home takes a bit of a back seat this time around. Still, we do discover more about her home life and, although she would never admit it, she is excited at the thought of seeing another time. That's important – as refreshing as having the companion being an unwilling traveller in the TARDIS is, it would grow quickly wearisome if she just hated the entire experience. 'Lux' marks an important turning point in the Doctor and Belinda's burgeoning friendship, while not abandoning her disquiet at this strange new life.
It's also, as we have alluded to a couple of times already, a bit of a wolf in sheep's clothing – an episode that initially plays like "traditional" Doctor Who, but is anything but. Take our advice: go in clean with this one, and watch it the moment that it drops on iPlayer and Disney Plus.
Doctor Who: 'Lux' will be released on April 19 at midnight PT/3:00am ET on Disney Plus and at 8am BST on BBC iPlayer, before airing later that day live on BBC One.
For more great new TV, check out our guide to the best new shows coming your way in 2025.