"There’s going to be a revelation. I’m not teasing. I’m not wrong-footing you – you’re about to learn something about the Doctor that you never knew before. And I think you’re in for a shock."
So wrote Doctor Who showrunner Steven Moffat in his Radio Times guide to the series-seven finale, and now we may just have discovered what the revelation in question will be – The Name of the Doctor.
That's the title of the concluding episode, as revealed on a new poster for the adventure, which also bills Alex Kingston as a guest-star, suggesting a return for her character River Song, one of the very few people who actually know the Doctor's real Gallifreyan name.
During his travels, the Time Lord has used aliases (John Smith, for instance) and we know his nickname at the Time Lord Academy was Theta Sigma. Matt Smith even ventured a guess at his real moniker – "Drasicanawhocius" – but the Doctor's true name has never been revealed.
In series four episode Forest of the Dead, River proved to the tenth Doctor that she knew him from the future by whispering his name to him, to which the shocked Tme Lord responded "There is only one reason I would ever tell anyone my name, only one time I could." Could the series seven finale be that time?
"His secret revealed", promises the poster, and while it doesn't specify which secret, if the clues point in the direction they appear to, Moffat may finally be ready to answer the question he has asked several times over in this series (and which Radio Times posed when the show first began) – "Doctor Who?"
The Doctor's Name, which will introduce new foes The Whispermen, is set to air on Saturday 18 May on BBC1.
See all four new Doctor Who posters here