"Doctor Who", the British science-fiction TV programme that started in 1963, has had twelve doctors so far. After Peter Capaldi, the current Doctor Who since 2014 (and who was a "risk" for the BBC because he was older than most of the doctors before him), announced that he would leave the show, fans called "to seize the opportunity to appoint a black or female actor as the 13th incarnation of the Time Lord".
Current writer Steven Moffat said that it would be "amazing" to have two non-white leading actors (via). Since shape-lifting is part of the narrative, more flexibility is given. The new cast certainly is "an obvious opportunity - at a time of urgent debate in British TV about diversity" (via).
“Of course there should be a female Doctor Who, but what we need is a man as her assistant. She has got to tell him what to do. He will need that leadership.”
Harriet Harman, former Labour deputy leader
“Before the BBC consider changing the lead role to a female Doctor, they should consider getting more female directors on the show. In the entire 50 years that Doctor Who has been on air there’s only been 10 female directors, which is a terrible reflection of the time we live in. Doctor Who’s very first producer was a woman, now there’s a success story for taking a risk. If they could do that a bit more now, it would be a better series as a result.”
Sebastian J. Brook, founder of Doctor Who Online
images of John Pertwee (1970-1974), Patrick Troughton (1966-1969) and William Hartnell (1963-1966) via and via and via