CLARA: Since when do you care about the Doctor?
MISSY: Since always. Since the Cloister Wars. Since the night he stole the moon and the President’s wife. Since he was a little girl. One of those was a lie. Can you guess which one?
—The Magician’s Apprentice
BILL: So, the Time Lords, bit flexible on the whole man-woman thing, then, yeah?
DOCTOR: We’re the most civilised civilisation in the universe. We’re billions of years beyond your petty human obsession with gender and its associated stereotypes.
—World Enough and Time
Still not ginger. After flirting with the Time Lords’ gender flexibility successfully thanks to the fantastic Michelle Gomez as Missy/The Master, Doctor Who broke the Internet by naming Jodie Whittaker as the 13th Doctor, the first woman to ever play the role. Whittaker joins incoming showrunner Chris Chibnall and an as-yet-unnamed companion. Chibnall and Whittaker have worked together previously on Chibnall’s creation Broadchurch, where Whittaker played Beth Lattimer for three seasons.
Although I am certain this choice will bring reams of criticism from fans not ready to see a female Doctor, I find this an interesting and thematically appropriate choice, given the Doctor’s century-long investment in saving his “man crush”-turned-woman which ultimately fails, crushing nearly two millennia of friendship. Each casting does not simply reflect the producer’s favorite actor for the part, but also a turn in the Doctor’s struggle, an exploration of his/her internal conflict. Perhaps seeing Missy make progress out of the darkness and nearly to the light gave the 12th Doctor hope that he too could purge the guilt plaguing his soul. Capaldi’s Doctor will bow in the Christmas special with the aid of the First Doctor, played by David Bradley. After her character’s apparent near-miss survival in the Season 10 finale, Pearl Mackie reportedly met with Chibnall; however, no word has been released regarding future appearances, and it is not expected that she will be the 13th Doctor’s companion.
— BBC One (@BBCOne) July 16, 2017