The plan to have a female Doctor in Doctor Who was in place at the BBC before Peter Capaldi left the series, it's been revealed. Doctor Who season 11 was a period of great change for the iconic sci-fi series, with Jodie Whittaker replacing Capaldi in the starring role and Chris Chibnall taking over from Steven Moffat as showrunner. However, Moffat's departure was announced slightly ahead of Capaldi's, and there was a period of time when it was thought that Chibnall might carry on with the Twelfth Doctor instead of casting his own.

Ultimately, this proved not to be the case and Capaldi stepped down from the role to let the incoming showrunner craft their own fresh take on the series. After feverish speculation, Chibnall cast Broadchurch actress Whittaker in the highly coveted part - the first female Doctor in the show's history - and the majority of fans reacted positively to the choice. Airing towards the end of 2018 and concluding with a New Year's Day special, Whittaker attracted plenty of acclaim during her first season in the TARDIS, as did new assistant Graham, played by Bradley Walsh.

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Whittaker has now revealed that she was told the 13th Doctor would be played by a female before Capaldi's decision to quit had become common knowledge. Speaking to her former regeneration, David Tennant, on the actor's accurately-titled David Tennant Does A Podcast With..., Whittaker stated:

"That wasn't outside of an inner circle either, that Peter Capaldi decided to move on. So, Chris [Chibnall] was like, 'It's funny that you bring it up, but the Doctor will be a woman. What about auditioning?'"

Whittaker revealed previously that Chibnall himself (who worked with her on Broadchurch) requested she try out for the role of the Doctor after he became showrunner, but it's interesting that Capaldi's impending exit wasn't widely known when this conversation took place. The decision to make Capaldi's successor female was clearly something decided early in the process either by the BBC, or by Chibnall after he came onboard. This version of events also corroborates previous comments made by Moffat, who claimed that he knew the next Doctor would be female during his final season on the show.

The decision likely also stems from the backlash Doctor Who received from some quarters after Capaldi was cast. While many fans were thrilled that an actor of Capaldi's caliber would be taking on the role of the renegade Time Lord, a vocal minority did criticize the show for casting another white male. Looking at some of the Capaldi-era stories however, it's perhaps abundantly clear that Doctor Who was gearing up to introduce a female Doctor. Not only did John Simm's Master become Michelle Gomez's Missy, but one scene on Gallifrey actually showed a Time Lord regenerating from a male into a female, definitively proving that gender could change during the process.

More: Doctor Who Season 12 Starts Production With New Cast Photo

Doctor Who season 12 is set to arrive in 2020 on the BBC.

Source: David Tennant Does A Podcast With...