Jodie Whittaker will be seen in her first scenes as Doctor Who confused as to why people are calling her "madam".
The actress will make history as the first woman to play the Time Lord when she takes over control of the TARDIS as the Thirteenth Doctor later this year.
A 52-second clip from her debut episode – due to be premiered at San Diego Comic Con next month – has been leaked online and shows the Gallifreyan hero struggling to get to grips with her new gender.
The Doctor is seen saying: "Why are you calling me madam? Oh… does it suit me? Sorry, half-an-hour ago I was a white-haired Scotsman."
Although the footage has sparked excitement among fans, the BBC moved quickly to get the footage removed from websites and social media channels before its official debut.
When it was revealed that new showrunner Chris Chibnall had chosen Jodie to become the new Doctor following the departure of previous series boss Steven Moffat and Twelfth Doctor Peter Capaldi the casting of a woman in the role divided opinion.
However, Jodie has urged viewers to give her a chance and not be "scared" about being the Doctor.
The 35-year-old star previously said: "It feels completely overwhelming; as an actor, as a woman, as a feminist, as a human, as someone who wants to continually challenge themselves and not be boxed in by what you’re told you can and can’t be.
"I want to tell the fans not to be scared by my gender because this is a really exciting time and ‘Doctor Who’ represents everything that’s exciting about change. The fans have lived through so many changes and this is only a new, different one, not a fearful one."
Jodie Whittaker questions identity in leaked Doctor Who clip
