The BBC are set to screen eight new episodes later this year and speculation is running rife that it will be the last time that fans get to see Whittaker in the role.
Becoming the first-ever woman to play the Doctor, the 39-year-old has been a pioneering figure and has become a favourite among fans over two acclaimed series to date.
Intriguingly, though, no actor has ever lasted more than three series in the role so it would comes as no surprise is she were to step down after this year's run.
In January, the BBC issued a statement and would not confirm if Whittaker would be heading into the role later this year.
Here, we take a look at who are the frontrunners to become the next Doctor if, of course, Whittaker is to leave her post.
Next Doctor Who betting odds
Olly Alexander - 4/6
According to Betway, Olly Alexander is the frontrunner to become the next Doctor - despite the fact that his agent has denied it.
Martha Kim wrote on Instagram: "Even though Olly is often contacted by Cybermen, I'm afraid I have to exterminate this speculation.
"As nice as it is to see interest in this story regenerate, it just isn't true. As odd as it might sound, Olly is focusing on his music, for the time being."
Michaela Coel - 10/1
Michaela Coel is another actor that has been tipped to take over from Whittaker, especially after her huge success over the past few years.
Richard Ayoade - 12/1
IT Crowd star Richard Ayoade is the third favourite to become the next Doctor - and would certainly bring a unique charm to its
Maxine Peake - 16/1
Silk actress Maxine is a slight wildcard on the list, but she could be exactly what the show is looking for.
Natalie Dormer - 16/1
Natalie's already conquered fantasy with her role as Margaery Tyrell in Game Of Thrones, so could it be her turn for a trip in the Tardis? Only time will tell.