The BBC has unveiled plans for more than 20 hours of programmes 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