Who is Lux in Doctor Who? Alan Cumming character explained

The animated foe, who trapped 15 people in film and attempted to do the same to the Doctor and Belinda during their adventure to 1950s Miami, revealed that he has an intriguing connection to some of the villains we met last season - from Maestro to Sutekh.

Thankfully, the Doctor and Belinda managed to defeat the tricksy animation and rescue the souls that had been lost to film - but not before Mr Ring-a-Ding revealed his true identity.

Here's everything you need to know!

Who is Lux in Doctor Who?

Lux Imperator, who disguises himself as cartoon character Mr Ring-a-Ding, is the god of light.

"I am the dazzle at the heart of the pantheon," he tells the Doctor. "I am the glint in the eyes of the mad. I am the last thing you see before you fall into the abyss. You think you can escape from me? You think you can escape light itself?"

He reveals he's part of the Pantheon of Gods, which also includes the Toymaker, Maestro and Sutekh from last season - making it clear that their reign isn't over.

Lux mentions that the Doctor has become renowned as the destroyer of the pantheon - and he clearly upholds that reputation as he and Belinda end up defeating Lux by drowning him in light.

Who voices Lux in Doctor Who?

Lux is voiced by Alan Cumming, who said of playing the role: "It is a truism that villains always get the best line, and are always much more juicy to play.

"I guess my favourite kind of villains are the ones that are misunderstood - while Mr Ring-A-Ding does not have any redeeming qualities, he does start out quite fun and endearing, so there is an arc to him that I enjoyed."

Interestingly, it's not Cumming's first role in the Whoniverse - he also played King James I in The Witchfinders.

Cumming has also previously said he was approached for the role of the Doctor at one point but turned it down as he didn't want to spend eight months of the year in Cardiff.

The actor is also known for a variety of different roles outside the Whoniverse, from TV series including The Good Wife and hosting the US version of The Traitors to films including GoldenEye, Emma, Romy and Michele's High School Reunion and Eyes Wide Shut.

He's also known as Nightcrawler in the X-Men film X2, a role he's set to reprise in the highly-anticipated film Avengers: Doomsday.

Doctor Who season 15 continues on 26th April 2025, coming to BBC iPlayer at 8am and airing at 7:20pm on BBC One.

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