Guess who the next "Doctor Who" is?

Matt Smith attends the preview screening of the first episode of the new series of "Doctor Who" at BFI Southbank on Aug. 14, 2012, in London.
Ben Pruchnie/Getty Images

You're guess is still as good as ours. The "Doctor Who" 'gods' are making us wait until a televised special to air on BBC1 at 2 p.m. ET to find out.

The actor (or actress) who will replace the departing Matt Smith will be revealed this Sunday in a live 30-minute special on at 7 p.m. BST -- hence the funky 2 p.m. U.S. time. The special, titled "Doctor Who Live: The Next Doctor," will be hosted by Zoe Ball and feature Matt Smith, producer Steven Moffat, in addition to celebrity fans and previous Doctors.

On its Twitter account, BBC One wrote: "The decision is made & the time has come to reveal who's taking over the TARDIS. For the last of the Time Lords, the clock is striking twelve."

Smith, who has played the iconic Time Lord since 2010 after taking over for David Tennant, announced that he was leaving the series in June, writing in a statement: "'Doctor Who' has been the most brilliant experience for me as an actor and a bloke, and that largely is down to the cast, crew and fans of the show. I'm incredibly grateful to all the cast and crew who work tirelessly every day, to realise all the elements of the show and deliver Doctor Who to the audience. Many of them have become good friends and I'm incredibly proud of what we have achieved over the last four years."Speculation has been swirling around Peter Capaldi, who has appeared on previous episodes of Doctor Who, as the frontrunner to be the new Time Lord, but there's also been rumors that Stephen Mangan ("Episodes") is in the running.

Smith's final official episode will be the series' 50th anniversary special in November, and he also recently revealed that he will appear in this year's Christmas special.

Speculation has been swirling around Peter Capaldi, who has appeared on previous episodes of "Doctor Who," as the frontrunner to be the new Time Lord, but there has also been rumors that Stephen Mangan ("Episodes") is in the running. Though we will have to be patient and let time tell us who the new Doctor will be on Sunday -- set your alarms.

In the meantime, tell us: Who are your favorite past Doctors?