Fans were left reeling when Peter Capaldi announced his decision to step down as Doctor Who after three years in the coveted role.
And now Whovians are already looking into the future to predict who may be stepping into his time-travelling shoes.
The three frontrunners tipped to pick up the Sonic Screwdriver are James Bond actors Ben Whishaw and Rory Kinnear, and comedian and star of The IT Crowd Richard Ayoade, with odds of 5/1, 7/1 and 6/1 respectively at bookmakers Ladbrokes.
However, some fans are calling for an actress to take over the hitherto male role, with Olivia Colman, Sheridan Smith and Helen Mirren all tipped to become the next Time Lord - or Lady.
But Miranda Hart is the bookies' favourite female, with odds of 8/1. If the comedian were to take the role, she would be the first female Doctor in the series.
Outgoing executive producer Steven Moffat has suggested a future regeneration of the Doctor could also be a woman, previously saying: 'I think the next time might be a female Doctor. I don't see why not.'
Bookies at William Hill have offered former Doctors Christopher Eccleston, David Tennant and Matt Smith at respective odds of 33/1, 20/1 and 16/1, while Harry Potter stars Daniel Radcliffe and Rupert Grint are tipped at 33/1 and 8/1 each.
So will it be Ben Whishaw swapping MI6 for the Tardis, Richard Ayoade trading crowds of IT geeks for crowds of Daleks or Miranda Hart falling into the police box?
The bookies' top four: Ben Whishaw (odds 5/1), Richard Ayoade (odds 6/1), Rory Kinnear (odds 7/1), and Miranda Hart (8/1)
5/1 - BEN WHISHAW: WILL Q SWAP MI6 FOR THE TARDIS?
Ben Whishaw is the bookies' favourite at 5/1
The bookies' favourite at 5/1, Whishaw has an impressive CV with credits including playing tech wizard Q in Bond blockbusters Spectre and Skyfall, and has previously been mentioned as a leading contender for the role of the Doctor.
In 2013 he won the best leading actor TV Bafta for his performance as Richard II in the first of the BBC's epic production of Shakespeare's history plays, and he was nominated again in 2016 for his performance in London Spy.
Should Bedfordshire-born Whishaw, 36, be interested in taking up the Time Lord mantle he may have the chance to get some tips from Capaldi as they reprise their roles in Paddington 2 later this year.
NOTABLE ROLES:
Layer Cake (2004)
Brideshead Revisited (2008)
James Bond (2012/2015)
The Danish Girl (2015)
Paddington (2014)
6/1 - RICHARD AYOADE: FROM HANGING OUT WITH THE IT CROWD TO THE DALEKS
Bookies odds on Richard Ayoade taking over are 6/1
The comedian, actor and director earned legions of fans and a TV Bafta for his portrayal of lovable geek Maurice Moss in hit Channel 4 sitcom The IT Crowd.
Ayoade also earned plaudits in the director's chair for 2010 rom-com Submarine and more recently voiced The Snowman in the BBC's reboot of the cartoon classic Danger Mouse.
While studying law at Cambridge he was president of the university's famed theatrical group, the Footlights, whose former presidents included Hugh Laurie, Sue Perkins and Eric Idle.
The 39-year-old is hot on Whishaw's heels with the odds for him taking the keys to the Tardis put at 6/1.
NOTABLE ROLES:
The Vicar of Dibley (2015)
The IT Crowd (2006-2013)
The Mighty Boosh (2003-2007)
The Life and Death of Peter Sellers (2004)
7/1 - RORY KINNEAR: THESPIAN ACTOR WHO KNOWS NOTHING ABOUT THE TIME LORD
Rory Kinnear: The odds on him taking the job are 7/1
Once tipped to take over from Matt Smith as the Doctor, the son of character actor Roy Kinnear is again among the favourites with the bookmakers.
He starred in the recent Bond films as M's Chief of Staff, Bill Tanner.
The 38-year-old said in 2013 that he had never watched Doctor Who and had no idea what it was all about.
However he would have had plenty of time to learn the difference between a Dalek and a Voord in the intervening years and was initially placed at equal odds with Ayoade on Tuesday.
NOTABLE ROLES:
The Imitation Game (2014)
Mansfield Park (2007)
James Bond (2008/2015)
Several notable television roles including Ashes to Ashes, Waking the Dead and Judge John Deed
The bookies' favourite at 5/1, Ben Whishaw has an impressive CV with credits including playing tech wizard Q in Bond blockbusters Spectre and Skyfall (pictured, alongside Daniel Craig)
Richard Ayoade: The comedian, actor and director earned legions of fans and a TV Bafta for his portrayal of lovable geek Maurice Moss in hit Channel 4 sitcom The IT Crowd and is third in line to become the next Doctor, according to Ladbrokes
STARS IN THE RUNNING TO PLAY THE NEXT TIME LORD - AND THE BOOKIES' ODDS
Bookmakers Paddy Power say actor James Norton (left) is their favourite to be next Dr Who with odds of 9/1, while Ladbrokes is offering odds of 16/1 that Idris Elba (right) will step into the role
According to bookmakers Ladbrokes, Ben Whishaw is the frontrunner to become the next Doctor Who with odds at 5/1.
Second, with odds of 6/1 is Richard Ayoade. Rory Kinnear, who also starred in the recent Bond films as M's Chief of Staff, Bill Tanner, comes in third, while Miranda Hart is fourth with odds of 8/1.
Other top actors in line for the coveted role, according to Ladbrokes, include Helena Bonham Carter (10/1), Olivia Colman (14/1), Michael Sheen (14/1), Idris Elba (16/1), Michael Sheen (odds 14/1) and James Corden (50/1).
However other bookies are offering slightly different odds.
Paddy Power has revealed actor James Norton is favourite to be the next Doctor Who.
Bookmakers are offering odds of 9/1 that Norton, who is best known for his roles in Happy Valley, Grantchester and War and Peace, will replace Peter Capaldi at Christmas.
Paddy Power has put the 31-year-old top of the list to replace Capaldi in the Tardis, closely followed by Ben Whishaw at 10/1 and Richard Ayoade at 11/1.
Norton has revealed that he would love to appear in Doctor Who, after previously appearing in the series four years ago in 2013.
He starred alongside Matt Smith's eleventh doctor as a Russian soldier named Onegin in the 80s-set episode Cold War, but his character was killed by Martian Ice Warrior Skaldak.
At the time he said in an interview with the Radio Times: 'It's no secret, my character met a fairly gruesome end in my Doctor Who episode. Maybe they could quietly recast me as someone else. It was a lot of fun. If Doctor Who would want me back I would happily to go back.'
Norton is also currently third favourite to be the next James Bond at odds of 10/3, behind Tom Hardy and Poldark's Aidan Turner. Now Paddy Power are offering 50/1 that Norton lands both roles.
A host of actresses have been put forward to play the next Time Lord - including, Olivia Colman (left) and Helena Bonham Carter (right)
THE PAST, THE PRESENT AND THE FUTURE: ONE OF THE WORLD'S BEST LOVED SCI-FI DRAMAS
With a history spanning more than five decades, Doctor Who has earned its place as one of the nation's best-loved series.
And as the world's longest running science fiction show, it has gained a cult following across the globe.
Generations have been gripped by battles between the Daleks and Davros, Cybermen, Zygons, new monsters like the Veil and old foes the Time Lords.
And the actors lucky enough to step into the coveted shoes of the Time Lord have gone on to become household names.
These include - among others - John Hurt (The War Doctor), Christopher Eccleston (Ninth Doctor), David Tennant (Tenth Doctor), Matt Smith (Eleventh Doctor)and Peter Capaldi (Twelfth Doctor).
Doctor Who was first broadcast on
BBC One on Saturday November 23, 1963.
Created as an educational family show to fit between the football results and evening entertainment programmes, the show was the brainchild of Canadian TV producer and BBC Head of Drama, Sydney Newman.
The first ever doctor from 1963 - 1966 was played by William Hartnell.
After an initial run of 26 years, the series was rested.
It returned for a one-off TV movie featuring the Eighth Doctor in 1996.
Doctor Who was fully resurrected in 2005 and has gone from strength to strength ever since.
In its 50th anniversary year, the series is watched by an estimated 80 million viewers in 206 countries.
It has been honoured by Guinness World Records as both the longest running and most successful science-fiction series in the world.
Capaldi announced that he will leave the Tardis in the Christmas special later this year, saying his time as the 12th Doctor has been 'cosmic'.
The 58-year-old will return for the tenth series of the relaunched show, with 12 episodes starting in April, followed by the Christmas special.
His final series will also end with the departure of writer and executive producer Steven Moffat.
Capaldi told BBC Radio 2: 'One of the greatest privileges of being Doctor Who is to see the world at its best.
'From our brilliant crew and creative team working for the best broadcaster on the planet, to the viewers and fans whose endless creativity, generosity and inclusiveness points to a brighter future ahead.
'I can't thank everyone enough.
'It's been cosmic.'
FANS - AND THE PRIME MINISTER - CALL FOR FEMALE TIME LORD
Could Miranda Hart, Billie Piper, or Captain America star Hayley Atwell - replace Peter Capaldi?
Fans called for a woman to replace Peter Capaldi in the Tardis when he departs.
Fan Brooke Wheeler wrote on Twitter: 'I think it's HIGH TIME that Doctor Who was a woman!! Regenerate female!', while another tweeted: 'Peter Capaldi's talented as hell and a legend, but CAN WE PLEASE HAVE A FEMALE DOCTOR.'
Sebastian Stoker suggested a former companion or female star could return as the Doctor: 'It is time. A female #DoctorWho plz. A nice twist that puts Alex Kingston, Billie Piper OR Catherine Tate in the role.'
Michelle Gomez, who plays Missy in the show, Captain America star Hayley Atwell and Sherlock actress Amanda Abbington are among the stars fans have said they would like to see in the role.
Vonnie Sandlan was among the fans calling for diversity in casting the next Doctor, saying: 'PLEASE let's have a new Doctor who isn't a white man.'
Former Doctor Who star Billie Piper has already ruled herself out of replacing Peter Capaldi. Piper, 34, played companion Rose Tyler opposite Christopher Eccleston and David Tennant's Doctors, reprising the role for later specials, and is one of the female stars fans have said they would like to see in the title role.
However, she said: 'I wouldn't like that responsibility, it's just too enormous, it's so much work.'
Piper said she would like to see another woman in the role instead, adding: 'They have been talking about that since I started, maybe it's one of those things they like to talk about that never comes to fruition, annoyingly.
'I think that would be a welcome turn, they have had a few different age groups and I think that would be the wise way to go. Whether they do actually go that way.
'Although I quite like the traditional format but I don't know how they would move forward with something fresh. I think it would be a wise opportunity.'
Piper said the role calls for 'someone really sassy' and added Captain America star Hayley Atwell, who is also a popular choice among fans on Twitter, would be a good option.
She said: 'She would be amazing and she's a friend of mine so I will call her and see what she's saying.'
Piper added she was sad to see Capaldi go, but said: 'It is a hard job and he's been there for four years and it does somehow keep it alive.'
Former deputy Labour leader Harriet Harman told a Westminster lunch the departure of Peter Capaldi meant it was time for a female Time Lord.
She said: 'Peter Capaldi was excellent – but yes, of course there should be a female Doctor Who. And what we need is a man as her assistant. She's got to just tell him what to do – he'll need that leadership.'
Prime Minister Theresa May believes it is for programme-makers to decide whether the next Doctor is a man or a woman, her official spokeswoman said.
'As someone who has been clear she enjoys Doctor Who, I think she will just want to see it continue and continue to be entertaining,' the spokeswoman told reporters who asked for the PM's view on the gender question at a regular Westminster media briefing.
'It's for the programme-makers to decide.'
Mrs May revealed her liking for the time-travelling Doctor in an interview with Radio Times about her Christmas Day TV viewing, in which she said: 'I always like to see Doctor Who on Christmas night, if possible.'
Peter Capaldi announces he is stepping down from Doctor Who
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