With less than 20 hours to go before the Twelfth Doctor is named, more details have emerged of some very special guests taking part in the show, scheduled to be screened live on BBC One, BBC America, SPACE Canada, and ABC Australia.
Current Doctor Matt Smith will be on hand in the studio to offer advice to the newcomer, where he will be joined by Fifth incarnation Peter Davison. Former Doctors will also be sending advice by video message, with Radio Times reporting Tom Baker will be taking part, and BBC One on Facebook indicating Colin Baker will be sending a message.
Current showrunner Steven Moffat will be in the audience, as one of only ten people who know the identity of the new Doctor, a closely guarded secret. Even the series brand manager Edward Russell has said the he genuinely doesn't know who has won the role, adding that "it's brilliant that we've kept the secret".
Former companions Katy Manning, Anneke Wills, Janet Fielding and Bonnie Langford will be hopefully be adding their input, along with veteran actor Bernard Cribbins, who played Wilfred Mott alongside the Tenth Doctor. A video message will also be screened from Doctor Who writer and actor Mark Gatiss.
The show goes on air at 1800 GMT on Sunday evening. That is 7:00pm in the UK, 2:00pm East Coast and 11:00am West Coast for North America, and 4:00am ET on Monday morning for those die hard fans in Australia (repeated at 8:30pm for those who aren't!).