John Hurt will play the Ninth Doctor in the 'Doctor Who' 50th anniversary episode.
The 73-year-old actor's alter-ego will be a regeneration of the Time Lord, which the character has forgotten about, in the special after Christopher Eccleston - who played the ninth incarnation of the Doctor in 2005 - refused to return for the episode after holding talks with showrunner Steven Moffat.
A source told The Sun newspaper: ''John will play the real Ninth Doctor. Christopher Eccleston has always been thought of as the Ninth Doctor but now that John has been revealed as the Ninth Doctor, it shuffles Eccleston's Doctor to be the 10th Time Lord, Tennant the 11th and Smith the 12th.
''It also means the Doctor's time is running out as he can only regenerate 12 times.''
John revealed earlier this week he will play ''part of the Doctor'' in a ''kind of trinity'' with Matt Smith and David Tennant, but the pair's Doctors will initially refuse to accept John's character is one of them until it becomes apparent thanks to their sonic screwdrivers.
The source explained: ''Steven loves a complex plot and there will be plenty of surprises along the way.
''The reason the Doctor has forgotten his ninth incarnation will become clear but it's to do with the Time War and his shame over his behaviour in it.
''Tennant and Smith's Doctors will at first refuse to accept Hurt is them -- until their sonic screwdrivers confirm it and announce, 'He's us. He's the ninth us'.''
John's Doctor has deliberately been given a style similar to both the Eighth Doctor - who was portrayed by Paul McGann - and Christopher's Time Lord.
A source said: ''John was given a very familiar look that goes half way between two regenerations.''
What's more, 'Doctor Who' will be celebrated at the Arqiva BAFTA TV awards on Sunday (12.05.13), in recognition of the programme's 50th anniversary.
Matt Smith and Jenna-Louise Coleman - who plays the current Time Lord's assistant Clara Oswald - have pre-recorded a sketch which will be screened at the ceremony to help introduce the brunette beauty on stage to present an award. Two Daleks will also be on the BAFTA red carpet.
Amanda Berry OBE, Chief Executive of BAFTA, said: ''There are only a handful of programmes that have the quality and longevity of 'Doctor Who' and the ability to put the nation on their sofas - or indeed behind them - year after year. BAFTA raises a toast to 'Doctor Who' on its 50th birthday this year.''
Steven added: ''I'm thrilled that BAFTA are including a special tribute to the show.''