The cast of the "Doctor Who" episode titled "Lux" (2025) includes:
- Ncuti Gatwa as The Doctor
- Varada Sethu as Belinda Chandra
- Alan Cumming as Mr Ring-a-Ding (voice), the antagonist and "God of Light"
- Linus Roache as Reginald Pye, the theatre's projectionist
- Lewis Cornay as Logan Cheever, a diner worker who helps investigate disappearances
- Anita Dobson as Mrs Flood, a recurring mysterious character
- Cassius Hackforth as Tommy Lee
- Ryan Speakman as Husband
- Millie O’Connell as Sunshine Sally (voice)
- Ian Shaw as Newsreader (voice)
- Lucy Thackeray as Renée Lowenstein
- Jane Hancock as Helen Pye
- William Meredith as Policeman
- Samir Arrian as Hassan
- Bronté Barbé as Lizzie
- Steph Lacey as Robyn Gossage
The episode was written by Russell T. Davies and directed by Amanda Brotchie
