Mary Poppins

When the Eleventh Doctor gathered magician props from the TARDIS, he placed them all in a large carpet bag which was bigger on the inside than the outside, saying he was glad he got it back from Mary Poppins. (PROSE: Magic of the Angels) Indeed, Tanya Adeola compared a bag with a large assortments of various useful things to "Mary Poppins' handbag". (PROSE: The Stone House)

Mary Poppins was the subject of a notorious film of the same name. The Sixth Doctor watched Mary Poppins on television one Christmas, during which he tried to fathom the aerodynamics of her umbrella; (PROSE: Christmas Special) this intellectual pursuit was shared by Andy Hansen, who once remarked that if Poppins had tried flying in the gale storms that were going on in 2015, she would have ended up in Norway. (PROSE: The Beast of Stalingrad) The Tenth Doctor later compared Poppins' style of flight to that of walking in zero gravity. (PROSE: I Am a Dalek) The Eleventh Doctor wondered — in the midst of a discussion about his fitness as a babysitter — if the twelve-and-a-half-year-old Kazran Sardick had seen Mary Poppins, but stopped himself before fully comparing himself to Poppins, saying that the analogy would have been "rubbish". (TV: A Christmas Carol)

To Gwen Cooper, Agnes Havisham looked like Mary Poppins' posher sister. (PROSE: Risk Assessment)

The Thirteenth Doctor later reflected that 's "Mary Poppins look" could blind some, but not her, to the fact that she was as dangerous as all of the Master's other incarnations. (PROSE: The Doctor vs the Master)

Behind the scenes

 * Missy's appearance is based upon that of the Julie Andrews version of Mary Poppins. In the stage directions from the script of TV: Deep Breath, Missy was physically described thus; "She's dressed a little like Mary Poppins." Furthermore, Missy imitates the style of Mary's arrival (floating down from the sky using an umbrella) in TV: Death in Heaven. This resemblance was eventually acknowledged in-universe by the Thirteenth Doctor in PROSE: The Doctor vs the Master.
 * The official Lethbridge-Stewart Novels Twitter account revealed that the author and creator of Lyndon Travers, Andy Frankham-Allen, came up with the name as a nod to P. L. Travers, the author of the Mary Poppins series of books. P.L. Travers' real name was Helen Lyndon Goff. The surname was given to the family of Margaret Travers, mother of Anne and wife of Edward, by Frankham-Allen.
 * Disney's 2018 film (a sequel to their 1964 film adaptation) featured David Warner, Jim Norton, Kobna Holdbrook-Smith, Noma Dumezweni, and Mark Addy among its cast.
 * During an online Q&A organised by the magazine WIRED in 2020, a partially-in-character Jodie Whittaker was asked about the fan theory of Mary Poppins being a Time Lord. Whittaker jokingly answered that in fact, it was perfectly possible that the Thirteenth Doctor hadn't been the first female incarnation of a very specific Time Lord.