Russell T Davies confirms length of Doctor Who season 15

Russell T Davies has confirmed the length of Doctor Who season 15 even though season 14 doesn't air until next year.

Fans of the long-running sci-fi show will be pleased to know that production is already underway for the fifteenth season which will be Ncuti Gatwa's second as The Doctor when he takes over from David Tennant following the 60th anniversary specials later this year.

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Writing in Doctor Who Magazine, Davies said: "Five of the next nine scripts, finished and planned. So all of the excitement above is already in the past tense for us."

A nine episode fifteenth season will be one episode longer than the fourteenth's eight episode run but still shorter than the typically thirteen-part series.

Davies also revealed that production was well underway despite season fifteen not expected until 2025: "And meanwhile, we’re filming the actual show! Back on the streets of Cardiff, to shoot the NEXT series."

Season 15 will also see the return of director Peter Hoar to the show who last directed an episode of Doctor Who in 2011 when he helmed the acclaimed episode A Good Man Goes to War.

Hoar has since worked with Davies on the critically acclaimed It's a Sin and Nolly.

Doctor Who's 60th anniversary specials are set to air on the BBC next month and feature Davies and Tennant returning to the show for the first time in a decade.

Tennant will not play his Tenth Doctor but instead the Fourteenth Doctor with Gatwa assuming the role as the Fifteenth Doctor.

The specials also see the return of Catherine Tate as Donna Noble and Bernard Cribbins' last TV appearance as her grandad Wilfred.

The three special episodes will also see Neil Patrick Harris portray the Toymaker, a villainous character last seen in 1966 when he was played by Michael Gough.

Watch below: David Tennant has admitted his Doctor Who return is his 'last shot' at the iconic role.