The BBC will exterminate weeks of fevered speculation on Sunday when it reveals the identity of the next Doctor Who in a live Time Lord extravaganza.
The Thick of It actor Peter Capaldi and Luther's Idris Elba are both lead contenders to replace Matt Smith as the 12th Doctor for the eighth series, expected to air next summer, according to bookmakers.
The rumours will finally be put to rest at 7pm in the live BBC1 show beamed to fans against a backdrop of a swirling vortex, Daleks and the Tardis.
The new Doctor will be interviewed by Zoe Ball in the half-hour special, which will also feature contributions from the show's executive producer, Steven Moffat, and Smith, who is bowing out after four years.
"The decision is made and the time has come to reveal who's taking over the Tardis. For the last of the Time Lords, the clock is striking twelve," said Moffat.
Fans are split over whether the BBC will go for a high-profile star or a relative unknown, as happened with both Smith and his predecessor, David Tennant.
Bookmakers have installed Capaldi, best known as the profanity-spewing spin doctor Malcolm Tucker in The Thick of It, as the favourite. Twitter users suggested a few Tucker-esque one-liners for Capaldi for the more family-friendly role, using the hashtag #tuckerwholines. "Oi, Dalek. Stuff your lollipop up your shiny metal arse, you mincing tin twat," offered Nathan Gower.
Cutting It star Ben Daniels is also in contention, as is Skyfall actor Rory Kinnear. David Harewood, Olivia Colman, Dame Helen Mirren and Billie Piper also get a mention.
Ben Stephenson, controller of BBC drama commissioning, said: "We can't wait to unveil the next Doctor. We've been using the codename Houdini."
