Doctor Who 50th anniversary episode to unite Time Lords past and present, John Hurt will star as the "dark Doctor"

BBC to air more than 20 hours of programs, with Matt Smith and David Tennant to appear in feature-length special

The BBC has unveiled plans for more than 20 hours of programs across TV and radio, culminating in a special feature-length edition to mark the 50th anniversary of Doctor Who.

The anniversary episode, called The Day of the Doctor, will unite the show's outgoing star Matt Smith with his predecessor David Tennant, alongside companions Jenna Coleman and the returning Billie Piper. John Hurt will star as the "dark Doctor" in the 75-minute episode, which will air on BBC1 on 23 November.

Rarely has the BBC devoted so many hours to celebrating a single show. Professor Brian Cox will explore the science of Doctor Who in a BBC2 special filmed in front of an audience of celebrity guests at the Royal Institution of Great Britain.

Cox will investigation the science of time travel, whether extra-terrestrial life exists in our galaxy and whether it would be possible to build a Tardis (police box disguise an optional extra).

Smith, who will leave the show after this year's Christmas special, said: "The Day of the Doctor is nearly here! Hope you all enjoy. There's lots more coming your way, as the countdown to the 50th begins now."

Blue Peter viewers will be given the chance to invent a new gadget that will feature in the next series, which is due late next year starring Peter Capaldi, best known as the foul-mouthed spin doctor Malcolm Tucker from The Thick Of It. A futuristic bleep machine presumably is out of the question.

BBC2 will broadcast Mark Gatiss's drama An Adventure in Space and Time, about the origins of the show, starring David Bradley, Brian Cox and Call The Midwife's Jessica Raine. In an hour-long special of The Culture Show, the dedicated Whovian Matthew Sweet will explore its cultural impact.

The BBC's director of television, Danny Cohen, said: "Doctor Who is a titan of British television and I'm incredibly proud to have it on the BBC. It's an astonishing achievement for a drama to reach its 50th anniversary. I'd like to thank every person – on both sides of the camera – who has been involved with its creative journey over so many years."

BBC3 will invite audiences to vote for their favourite monsters and villains across a weekend of programming, and BBC4 will broadcast the first ever story, starring William Hartnell, with all four episodes to be shown in a restored format not previously broadcast in the UK.

The Doctor Who showrunner and lead writer, Steven Moffat, said: "Fifty years has turned Doctor Who from a television show into a cultural landmark. Personally I can't wait to see what it becomes after 100."

Graham Norton will present his Saturday morning Radio 2 show live from the Doctor Who 50th birthday celebrations event in London's Excel exhibition centre, and there will be documentaries about the Doctor on Radio 1, Radio 2, Radio 4 and Radio 4 Extra.

The 50th anniversary edition of Doctor Who will feature the timelord's most infamous foes, the Daleks and the Cybermen, as well as the Zygons, the shape-shifting monster race who first appeared in the series in 1975.

© Guardian News and Media 2013

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